OK... this saved me buying a new computer. Had no pulse on no. 2 injector causing misfire so after testing wires assumed computer was faulty... until I checked out this video and checked pulse on initial startup... sure enough pulsed a couple of times and shut off... swapped the brand new ignition coil on that cylinder with an old spare and bingo problem solved. Tip from me is don't assume new parts are good. Thank you ScannerDanner
@@ScannerDanner i have a 1999 Nissan frontier 3.3 and the coil is in the distributer, will there be a flash at start up with that like the individual coils does and also i eont have a OEM distributer can that cause a single misfire and i also have a misfire on #2 cylinder with no pulse but has 12v going to it, but just hadnt got to check to see if flash at startup yet and didnt even know if there would be a flash with just one coil
Scannerdanner, I buy and sell cars for extra income, I must say I have been able solve many a problems using ur methods of testing. I don't even have ur book yet, just studying your teachings on UA-cam .. So to hell with itt technically institute.. I know sum of those cats come out as confused as they went in..Thank u for sharing ur knowledge with the rest of us..
hi paul thanks for this video and others this was a massive help to me and i managed to fix my ecu problem keep up the great work no 1 guy best regards from the uk
Excellent, thorough explanation with related exceptions, a.k.a. "Gotcha" that under score the necessity of thorough knowledge of the complete circuit i. e. are ASD's involved... Very very good lecture. Thomas Jones, New Olreans
I've been trying to troubleshoot a 91 nissan 240sx with high fuel pressures and white smoke/fuel coming out the exhaust. Replaced fpr twice with same condition. I'm looking into checking the injectors. I'm a novice when it comes to automotive diagnostics. This is definitely a learning experience
most likely from an ignition system misfire. the computer will shut the injector down to protect the catalytic converter. these are notorious for coil problems as well as plugs and wires
@MrGtech777 I think I just sent you an email. But you should have received an email that contained both your license code and web address for book access. If you lost it contact me through my website and I'll get it back to you. Thank you very much for the compliment and the purchase.
Cheers man, I thought it would melt or burn it out too, thanks, Ive read that your type of picoscope/oscilloscopes the only way to measure common rail diesels injector pulse with an amp clamp, like with the testing of injectors normally..I was just trying to find a way with my multimeter. I just watched your P0205 code- mechanical-stuck open injector, the code breaker book points to an open but turned out that it was a short to ground in your video, I hope its as simple as looking to see a break
after watching this video I went ahead to try it on my car, a 95 corolla, and the car runs but there is no control. the testlight had a constant light on both wires. I completely understand what was taught on this video but I'm a lost in applying it. I'm going to check the control circuit for a short then do the necessary checks at the computer and see what's my case here. Great video. I still learned alot
"runs but there is no control" I am assuming you are dealing with a single cylinder misfire? BTW it is normal to see a constant light on both wires (depending on your test light impedance). This would not be a short but an open. One side should be pulsing. Watch this video on testing the injector circuit. This one has an open in the injector winding so a little different than you describe for yours but still valuable information. ua-cam.com/users/edit?o=U&video_id=mmRhcVkJdeQ
Hey scanner danner! What do you think about unplugging the fuel pump connector to prevent back feeding on the circuit during an injector short to ground test on the feed side with a test light?
+Doug Terry sure, you could do that. great question my friend. it shows you were following very well. one other thing to consider, on a Chrysler (ASD circuit), you can get a back feed through the O2 heater circuit too.
9:00 yeah i witnessed the computer doing this first hand - turning off the injectors within a few seconds of restarting, once it sees the misfires again. In my case it was a clogged driver's side cat, so the only way I could get home was to stop and restart it and get a block or two, then repeat. (about 25 times, lol)
Hello, Paul. You are not mentioning a short to voltage on the control wire. If the control wire is powered by another circuit, you will get 12 v on the control wire, which will keep the pcm from grounding the injector and can also result in pcm driver damage if the pcm does not have high protection against short like that. That is my analysis of the circuit. You are the man a lot of mechanics on you tube copied on. You have the final word.
That is a variable for sure but extremely unlikely, (so much so, I've never seen it) and when or if that would happen, it would definitely cook the driver in the PCM. I'm not sure it was necessary to cover that here but maybe?? How would one catch this? First it would depend if the short to voltage is on a circuit that is 1)hot all the time 2)hot with the key on 3)hot with it running only (like an ASD relay circuit) Second, in your testing you would find 12v on both injector wires with the injector unplugged, which could be a bias voltage (normal) or an actual problem. The separating test would be do BOTH wires12v readings light your test light?(incandescent) If yes, then you found your issue and you better fix it before going any further. Thanks so much!
Hello scaner I've recently started to watch your UA-cam videos I must say that you are a genius to be able to dumb it down enough for me to understand . I have a question to ask I'm getting a intermittent miss injector fail i know what one it is it's bad enough that it blows clouds of smoke when it's failing what is the best way to diagnose it ...for a home work shop?
are you sure it is the injector causing the white smoke? it will smell like raw fuel if it is. a head gasket can also cause white smoke. IF it is the injector you have to test it as I described in this video DURING the event to determine where the problem is. I have never seen an injector stick open on its own, it has always been a short to ground in the wire or driver
I have found the problem it was a driver I changed the ecu it ran much better although not quite right under further inspection I found that a terminal in the ecu connector was loose wich I think it may of burnt the driver out Thank you for your help it's really appreciated.
Would all of this also apply if the engine won't start? I have a 89 S-10 Blazer that im trying to get running again,has been sitting for about a year.I have fuel going upto to the injectors but no fuel spray.Used the Noid light and it flashes every time the engine tries to start.
How about if both wires stay on I check with the tester they both give me power on each side of the injector No Flash. When I turn the key on it does turn on with the tester inside. Touching ground
Hi Paul I have a P0204 code on a Vauxhall/Opel common rail Diesel engined vehicle. I hear that common rails voltage feel to the injector is between 80-120volts, can I used a noid light in this situation, as I haven't found an answer online. Thank you
1991 Saturn SC 1.9L 4cyl. PFI. I have an occasional sputter, no start condition. When car failed it was like someone turned off the key. All injector coil resistance are perfect. System type: All 4 injectors fire at the same time, not sequentially. I disconnect all 4 injectors and the noid light flashes on each of 4 injectors. I reconnect 3 of the 4 injectors, noid light on forth and there is no flash. I say this is a weak driver in the ECM. (flashes when the driver is not loaded up, does not flash with the driver is loaded up) Do you agree with a bad driver in the ECM?
the reason I said that I think it might be a short is because of evidence like it runs and the exhaust smell rich of fuel, so that left me to think that maybe the driver is constantly grounding the injectors, yep my testlight did not flicker on any of the injectors. However you pointed out that the impedence of my testlight maybe a variable in my case, so I'm going to try using another testlight to see where's my next direction. Oh it has a misfire, so maybe I'm going the wrong direction here but still not seeing control on those injectors with my testlight certainly raises a brow.
I got a 2005 300c 5.7 chrysler So ignition to ON position the test dosnt turn on on problem injector nor other ones but when running others pulse and problem injector stays on lots of fule coming out exhaust like your video of the white van raw fuel white smoke
You only need to ask this one time, I see all the comments. Disconnect the injector that is stuck open and connect a test light to battery positive and touch on the control wire. If it lights constantly, that circuit is shorted to ground. Now disconnect the PCM and see if the light goes out. If it does, it is a shorted driver, if it doesn't it is a shorted wire
@@MustangFourSix as long as the injector was also unplugged for the test, and that this is a sequential injection system (individual control wires for each injector), your done, that driver is cooked in the ECM. Make sure that injector is not shorted too! A quick resistance test and compare to a know good one works
@ScannerDanner how would I know if it's sequential system all the injectors have one wire that is the same all across other Injectors brown and yellow line
@nesgarl1 I am by no means a certified technician, that's not my nature of business when it comes to cars.. Although I have nt taking the ase test I know a little bit, buying and selling cars u half to. If its a system I'm not familiar with I study it thoroughly learning the theory of operations.. And through the teaching of the great Scannerdanner I have learned sum shortcuts. I apologize if i have offended u or anyone with my comment..
Last added comment on common rail is the pressure in the system is 30,000psi!! they are right into the cylinder so that's probably why the voltage and windings within the injector are 100volts approx
I don't think you can, it would burn out the noid light bulb. They may make a special type of bulb for your application. Wish I knew more about the diesels so I could advise you better than this
Dan I need your help. What are the two fat red wire leads that plug-in?. (Boshe injector Mercedes). On a 05 smart car CDI diesel..I've been trying to find out for 2 years now so I can diagnose why I have a no spray situation at the injectors. I don't want to just start poking around and blow the ECU. I've TRY to contact boshe in Germany, local Mercedes dealers.. injector service shops, etc... nobody can tell me...I'm guessing one is feed , the other is pulse((theres continuity between the two)) and gets ground through the body. But still not certain 🤔
Let's move this to my forum www.scannerdanner.com It is free to join and we can definitely help you. I have 28k global members and hand picked moderators who've been with me for years and know my material inside and out and are there to help me help you guys. It is just too difficult to offer back and forth messages here on UA-cam with stuff like this and we also can't share pictures and images here like we can on the website. Hope to see you there!
Hey sir danner how are you. I just want to know what do you mean by injector on hold time ?? And thank you so much for your help. Greetings from Morocco 🙏🙏
Hey Gang, I just swapped out the four original Multec I injectors on my '94 Saturn SL2 (238K miles). It was the first time I ever removed a fuel rail and injectors. So it was a learn as I go project.I replaced the fuel pressure regulator as well, with the a AC-Delco unit, since it was original with 238K miles. The FPR didn't owe me anything, right?. I don't have a scanner. I do have a Fluke 87-V with basic leads, 'noid and a test light. Upon start up I found cylinder 4 to be “dead”. I pulled out the plug lead and no RPM change. As I had new plug wires I swapped out the old ones (the old wires were due), and Scotch Brite cleaned the coil terminals. I bought a noid light kit and found that the #4 injector pig tail had a steady light, not flashing, as compared to cylinders 1-3. I DID NOT realize the significance of this steady light at the time. I got an RMA from the vendor and got another injector shipped. Put in the injector and no joy. It was then I found this video and realized I might have a short to ground. I think my situation is the #3 bullet point. As I've moved the wiring harness around for the fuel rail, MAP sensor, and TPS, I pondered whether I cracked some old insulation and created said short to ground. With KOEO I pulled the plug from PCM (plug port B-16 solid green for negative side of the injector #4 circuit), with the battery connected I affixed my test light to the positive battery terminal and the (-) side of th #4's pigtail. No light. I'm assuming therefore the negative side of the circuit is NOT shorted to ground, but I have a bad computer. When the engine runs I get the thick cloud of white smoke out back, so I know the injector is continuously on, and I hear no clicking from the injector via the screwdriver to the ear. I have a reman'd unit offered to me for $80, via E-bay from a credible local vendor. But before I buy it I'm wondering if anyone has some thoughts. Paul, you out there? Any help appreciated.
I always try to answer those who have clearly done there homework. Nice job so far! So you pulled the one single injector control wire from the PCM connector correct? Then you connected test light to b+ and touched the control wire harness side and it was not lit?
ScannerDanner Premium Sorry, I pulled the whole multi-plug out of the PCM. Then with battery connected I attached the test light to the + battery terminal, and the light's probe to the green ( - ) side of the #4's pigtail. My car is a Saturn SL2 1994 DOHC. I think it may have that ASD relay, but I'm not sure. Oh yeah, thanks for the awesome help and advice you do here. Another edit: According to my Chilton book the plug port is B-16, but the Haynes book says D-16. Go figure.
ScannerDanner Premium Addendum: I pulled the entire plug out of the PCM. Then I connected the test light to B+ and to the - side wire harness of #4 I got no light. Sorry, I forgot to include that. I also forgot to mention that I put a screwdriver to my ear and heard clicking for injectors 1-3, but nothing on #4. I suppose another question I have, if the PCM indeed packed it in, is why it did so when I changed the injectors. When did I do somewhere to cause it? I had trouble removing the #4 plug, it was stuck, and the spring retaining clip was worn out. I broke the plug getting it off, and I wonder if shorted the circuit. Maybe I did. I have a spare pigtail on the circuit at the moment, just wire nutted, but I have to trim off the excess slack and solder/shrinktube it on permanently once I get the car roadworthy again.
RandallFlaggNY did you see this one? ua-cam.com/video/jsl531-6q-A/v-deo.html what you have sounds like a shorted PCM driver but watch this video to be sure
What about a misfire on two cylinders that are next to eachother that started incredibly suddenly? (Drove to go into restaurant to pick up food truck was fine. not even 2 minutes later back out to my truck and it's missing) Check Engine light flashes on the freeway sometimes but its always missing. Scan tool live data counts misfires on #2 and #4 on my 98 Chevy K1500 5.7. Fuel pressure was strong 60 psi. Compression was about equal to known good cylinders. (although I tested when engine was cold.)
I have this exact situation going on! I had white smoke that smelled like raw fuel injector #6 stuck wide open I shot the parts cannon at it...new plugs, wires , coil, injector, pvc even replaced the fuel pump....The noid light would light up. One day it just started running fine again, and now fast forward a year...I’m getting same cylinder misfire on #6 cylinder, but no more white smoke instead now noid is NOT working.. I’m getting 14 volts on feed side and 0 volts on the control wire... I did what you said and followed wire to computer and it’s saying 0 volts, however I can’t go any further the wires go up down and around the tight area under the battery box 09 Escalade hybrid .... does this wire go to fuse box? I believe it’s a shorted wire because it would only act up after it rained a few days...
Remember, if that control wire is shorted to ground, that injector will be spraying fuel constantly! And you will absolutely have white smoke pouring out if the tailpipe
ScannerDanner that’s what it was doing a year ago and all symptoms went away and all of a sudden one rainy hot muggy midwestern day it came back in same #6 cylinder, however now instead of stuck open spraying fuel it it’s not clicking at all... I can feel the injector not clicking inside like the rest. I swap with cylinder #4 and it starts working. I’m thinking there was a corroded or shorted wire that finally snapped or something. when it used to act up I could tug on the harness and make it fix itself, but that won’t work anymore ...another indication it’s most like a broken or corroded wire or a loose connection.
@@vunit8213 I understand what it was doing before and there is no question you have a harness issue that was never fixed, however, if you have 14v on the feed and 0v on the control, measured right at the injector and you are sure the injector is not energized, there is only one cause for that, an open in the injector winding. You said when you switch it to another cylinder that the injector starts working? So when #6 is moved to #4, the #6 injector works? A corroded wire that would lead to an open circuit, you would read battery voltage on both the feed and control wires when measured at the injector, but 0v at the computer.
scanner danner let me ask a question. my brother has an 01 4x4 silvarado. 1 whole side is getting pulse by ground but is only getting 1.8 volts on positive and it needs 14. I have checked the relay and notice 14 on one side 1.8 on another and 12 on another. I have tested a good 99 sierra and know for a fact 3/4 prongs on the asd relay will have 14 volts. MY question is where would the 1.8 come from originally that goes from the relay to the positive injectors on all of the passenger side. also*** the other side of the engine all have 14 volts when running on the positive side of the inj. if this makes sense please answer I think its coming from fuel pump module but am no expert. would love help
in a nut shell. on a good running same year truck. i know there is negative power pulse fluctuation, also I know there is 14 volts on all positive side of all injectors. on the bad running truck I have 14 volts on all inj on driver side and only 1.8 on all positive side inj from the passenger side. also I know from a good truck that 3/4 prongs on the asd fuel relay will have 14 volts when running. the bad truck only has (2) sides with 14 and a 1.8 that matches the failed passenger side. so where would the 1.8 volts come from. does it come from the fuel pump module or comp?
5.7 hemi code p0305 I changed the coil spark plug and swapped injector with a good one same code!! I also did a compression test 220psi!! Know what please help me!!! The engine shakes lightly but when going up an incline or giving it heavy gas it goes into a heavy Shake an engine light flash
I have code p0208 #8 injector circuit an p0308 #8 misfire..... while car running pulled injector 8 connector off an there no change in idle sound, Pulled #6 an there was a change in idle sound.... Put a noid light on 8 an no light....loosing my mind with this
Sir, I have one doubts why there is 3V on one side of fuel injector and not 12V in my i20 2011. There are no issues in my i20. Just curious to know whether it should be 3V or 12V? With engine off and key at ON position, the connector harness is connected to the fuel injector. Now, one end of multimeter is connected to ground and other end to one side of the fuel injector. The multimeter shows 12V, and other side of the connector shows 3V. Is this 3V supposed to be 12V and dropped to about 0V only when injector is switched on. Please note the injector is a computer controlled ground side switch. Same result for the remaining 3 injectors. I'm really surprised why it's showing 3V rather than 12V on a ground side switch.
@@ScannerDanner yes both go to the ecm. The injector seems to be a ground side switch. With connector still plugged, one side read 12v and other side read 3v with engine off and key at on position.
@@ScannerDanner it would be really great if you could make new videos explaining why there's 3v on one side in a computer controlled ground side switch circuit.
Hi so I'm looking at your video and im having a problem with my 1988 2.8 Chevrolet s10 and the noid light is not coming on. The truck has spark can you please help.
Take a test light connected to battery positive with the key on and touch on and off the purple white wire coming from the ignition module. If the injectors fire, replace the module ua-cam.com/users/edit?o=U&video_id=mxPdxGqRWvc
I have a 96 350c.i. 5.7 LT1 in my jeep. Runs perfectly at cold start, when I hit running temp at about 170°- 180° i start getting a flutter and bogs almost like bad iac she's rich smelling. My reader says multiple misfire and my iat is -38°.
Ok so after verifying no clicking at any injector on pass side ( tan wire ) and still no pulse at connectors at each injector. I went to PCM to pin 58 ( tan wire ) back probed pin and went to batt pos and still no pulse. Although back probing pin 59 ( White wire, bank that's working ) I get the pulse, confirming driver is sending signal out on that side. Also confirming driver for tan wire pass side not firing injectors is bad. I'ma call it a bad PCM driver and going to swap PCM out.
Let's make sure it is not some type of intentional shut-down of the injectors. The computer will do this when it recognizes a misfire to prevent the cat from melting down. The key in identifying this condition is to test for injector pulse immediately on start up. The computer will always try again on initial start up before shutting them back down.
@@ScannerDanner here is the post I made in the forum, shows pics ect. seems some bad wires pos to pulse wire crossed and shorted pcm. it is obd1 the other side works fine and is on a separate pulse wire. I did a batt disconnect, then reconnect and had someone turn key over as I was checking for pulse on the side in question. Just to make sure it wasn't an auto shut down. Then I went to pcm/ecm. Pulses on side that works pin 59 but not on the side that don't pin 58. Found a good used ecm for 35.00 so I'ma ( lol ) swap it because it's cheap enough and being obd1 and same MT/FED and part number as well as no programming because of age and type. Your videos have helped me greatly with diagnosing this obd1 system. Let me know what you think after looking over the post in the forum linked below. www.scannerdanner.com/forum/search.html?query=engine%20running%20on%20one%20side&searchdate=all&childforums=1&catids=4
It is becoming more and more difficult to answer questions here. I have 80,000 people asking me for help now. So I have created a forum to help you guys better. It is free to join and we can exchange pictures, wiring diagrams and waveforms if needed to help guide you through the process of troubleshooting your vehicle. Thank you so much! Hope to see you there. Paul Danner (ScannerDanner) www.scannerdanner.com/forum/post-your-repair-questions-here.html
+scannerdanner I guess the moral of the story here, is it pays to know your circuit designs. Diagnosing can be simple when you have the road map in front of you!
On a throttle body with obd-1 with just injectors a noid light helps....on obd-2 you really need a scanner to find it. Much faster....take it to a dealer as most new cars you are pretty much never gona find the problem for the diy.
OK... this saved me buying a new computer. Had no pulse on no. 2 injector causing misfire so after testing wires assumed computer was faulty... until I checked out this video and checked pulse on initial startup... sure enough pulsed a couple of times and shut off... swapped the brand new ignition coil on that cylinder with an old spare and bingo problem solved. Tip from me is don't assume new parts are good. Thank you ScannerDanner
+MrClusterfuk sweet
@@ScannerDanner i have a 1999 Nissan frontier 3.3 and the coil is in the distributer, will there be a flash at start up with that like the individual coils does and also i eont have a OEM distributer can that cause a single misfire and i also have a misfire on #2 cylinder with no pulse but has 12v going to it, but just hadnt got to check to see if flash at startup yet and didnt even know if there would be a flash with just one coil
Scannerdanner, I buy and sell cars for extra income, I must say I have been able solve many a problems using ur methods of testing. I don't even have ur book yet, just studying your teachings on UA-cam .. So to hell with itt technically institute.. I know sum of those cats come out as confused as they went in..Thank u for sharing ur knowledge with the rest of us..
Thanks again for another great video Paul!
Your the best teacher I've ever had.
Yes. If you have pulse and no spray with good fuel psi try tapping on the injectors they are probably stuck shut from sitting.
Paul is the very best teacher. Thanks for your Videos. All good for you and your Family. Thanks.
Great teacher with will explanation on fuel pump relay problem . thanks to you Paul
hi paul thanks for this video and others this was a massive help to me and i managed to fix my ecu problem keep up the great work no 1 guy best regards from the uk
Excellent, thorough explanation with related exceptions, a.k.a. "Gotcha" that under score the necessity of thorough knowledge of the complete circuit i. e. are ASD's involved... Very very good lecture. Thomas Jones, New Olreans
Thank you Dirk!
Fantastic and understood everything including the asd relay. Well done !!
Another awesome video with valuable knowledge.thank u so much👍🏽
I've been trying to troubleshoot a 91 nissan 240sx with high fuel pressures and white smoke/fuel coming out the exhaust. Replaced fpr twice with same condition. I'm looking into checking the injectors. I'm a novice when it comes to automotive diagnostics. This is definitely a learning experience
@TRcustomengineering No problem friend thank you!
DEFINITIVAMENTE ERES BUENO EN LO QUE HACES.
Scannerdanner# thank you so much for sharing this information
most likely from an ignition system misfire. the computer will shut the injector down to protect the catalytic converter. these are notorious for coil problems as well as plugs and wires
Thanks your video really helped the Blazer is now running again.Had to buy new
@MrGtech777 I think I just sent you an email. But you should have received an email that contained both your license code and web address for book access. If you lost it contact me through my website and I'll get it back to you. Thank you very much for the compliment and the purchase.
Cheers man, I thought it would melt or burn it out too, thanks, Ive read that your type of picoscope/oscilloscopes the only way to measure common rail diesels injector pulse with an amp clamp, like with the testing of injectors normally..I was just trying to find a way with my multimeter. I just watched your P0205 code- mechanical-stuck open injector, the code breaker book points to an open but turned out that it was a short to ground in your video, I hope its as simple as looking to see a break
nice. From Peru, thnks
I never comment on videos but bro!..... you saved me lol,,
Sweet! What was it?
after watching this video I went ahead to try it on my car, a 95 corolla, and the car runs but there is no control. the testlight had a constant light on both wires. I completely understand what was taught on this video but I'm a lost in applying it. I'm going to check the control circuit for a short then do the necessary checks at the computer and see what's my case here. Great video. I still learned alot
"runs but there is no control" I am assuming you are dealing with a single cylinder misfire?
BTW it is normal to see a constant light on both wires (depending on your test light impedance). This would not be a short but an open. One side should be pulsing.
Watch this video on testing the injector circuit. This one has an open in the injector winding so a little different than you describe for yours but still valuable information.
ua-cam.com/users/edit?o=U&video_id=mmRhcVkJdeQ
Hey scanner danner! What do you think about unplugging the fuel pump connector to prevent back feeding on the circuit during an injector short to ground test on the feed side with a test light?
+Doug Terry sure, you could do that.
great question my friend. it shows you were following very well.
one other thing to consider, on a Chrysler (ASD circuit), you can get a back feed through the O2 heater circuit too.
9:00 yeah i witnessed the computer doing this first hand - turning off the injectors within a few seconds of restarting, once it sees the misfires again. In my case it was a clogged driver's side cat, so the only way I could get home was to stop and restart it and get a block or two, then repeat. (about 25 times, lol)
Great explanation........thank's
Hello, Paul. You are not mentioning a short to voltage on the control wire. If the control wire is powered by another circuit, you will get 12 v on the control wire, which will keep the pcm from grounding the injector and can also result in pcm driver damage if the pcm does not have high protection against short like that. That is my analysis of the circuit. You are the man a lot of mechanics on you tube copied on. You have the final word.
That is a variable for sure but extremely unlikely, (so much so, I've never seen it) and when or if that would happen, it would definitely cook the driver in the PCM.
I'm not sure it was necessary to cover that here but maybe??
How would one catch this? First it would depend if the short to voltage is on a circuit that is
1)hot all the time
2)hot with the key on
3)hot with it running only (like an ASD relay circuit)
Second, in your testing you would find 12v on both injector wires with the injector unplugged, which could be a bias voltage (normal) or an actual problem. The separating test would be do BOTH wires12v readings light your test light?(incandescent) If yes, then you found your issue and you better fix it before going any further.
Thanks so much!
Thank you ! By the way, most of the things I learn is from you.
Hello scaner I've recently started to watch your UA-cam videos I must say that you are a genius to be able to dumb it down enough for me to understand . I have a question to ask I'm getting a intermittent miss injector fail i know what one it is it's bad enough that it blows clouds of smoke when it's failing what is the best way to diagnose it ...for a home work shop?
are you sure it is the injector causing the white smoke? it will smell like raw fuel if it is. a head gasket can also cause white smoke. IF it is the injector you have to test it as I described in this video DURING the event to determine where the problem is. I have never seen an injector stick open on its own, it has always been a short to ground in the wire or driver
I have found the problem it was a driver I changed the ecu it ran much better although not quite right under further inspection I found that a terminal in the ecu connector was loose wich I think it may of burnt the driver out Thank you for your help it's really appreciated.
In some case PCM disable the injector driver if misfire occurs caused by ignition system to protect the CAT .
Would all of this also apply if the engine won't start? I have a 89 S-10 Blazer that im trying to get running again,has been sitting for about a year.I have fuel going upto to the injectors but no fuel spray.Used the Noid light and it flashes every time the engine tries to start.
How about if both wires stay on I check with the tester they both give me power on each side of the injector No Flash. When I turn the key on it does turn on with the tester inside. Touching ground
Any idea where I might be able to find a Noid light kit for Direct Injection vehicles?
Hi Paul I have a P0204 code on a Vauxhall/Opel common rail Diesel engined vehicle. I hear that common rails voltage feel to the injector is between 80-120volts, can I used a noid light in this situation, as I haven't found an answer online. Thank you
1991 Saturn SC 1.9L 4cyl. PFI. I have an occasional sputter, no start condition. When car failed it was like someone turned off the key. All injector coil resistance are perfect. System type: All 4 injectors fire at the same time, not sequentially. I disconnect all 4 injectors and the noid light flashes on each of 4 injectors. I reconnect 3 of the 4 injectors, noid light on forth and there is no flash. I say this is a weak driver in the ECM. (flashes when the driver is not loaded up, does not flash with the driver is loaded up) Do you agree with a bad driver in the ECM?
the reason I said that I think it might be a short is because of evidence like it runs and the exhaust smell rich of fuel, so that left me to think that maybe the driver is constantly grounding the injectors, yep my testlight did not flicker on any of the injectors. However you pointed out that the impedence of my testlight maybe a variable in my case, so I'm going to try using another testlight to see where's my next direction. Oh it has a misfire, so maybe I'm going the wrong direction here but still not seeing control on those injectors with my testlight certainly raises a brow.
Orlando, post your questions to my forum. I'll try to help you more over there.
www.scannerdanner.com
I got a 2005 300c 5.7 chrysler
So ignition to ON position the test dosnt turn on on problem injector nor other ones but when running others pulse and problem injector stays on lots of fule coming out exhaust like your video of the white van raw fuel white smoke
You only need to ask this one time, I see all the comments.
Disconnect the injector that is stuck open and connect a test light to battery positive and touch on the control wire. If it lights constantly, that circuit is shorted to ground. Now disconnect the PCM and see if the light goes out. If it does, it is a shorted driver, if it doesn't it is a shorted wire
@ScannerDanner I did as you asked + to bat and other to stuck open injector control wire light stayed on then I disconnected pcm and no light at all
@ScannerDanner sorry for all the questions noted for next time I have a question thank you for helping me out I appreciate it alot.
@@MustangFourSix as long as the injector was also unplugged for the test, and that this is a sequential injection system (individual control wires for each injector), your done, that driver is cooked in the ECM.
Make sure that injector is not shorted too! A quick resistance test and compare to a know good one works
@ScannerDanner how would I know if it's sequential system all the injectors have one wire that is the same all across other Injectors brown and yellow line
I have low impedance Toyota injectors so the harness plug puts out very little voltage can these be test with a noid light ?
@nesgarl1 I am by no means a certified technician, that's not my nature of business when it comes to cars.. Although I have nt taking the ase test I know a little bit, buying and selling cars u half to. If its a system I'm not familiar with I study it thoroughly learning the theory of operations.. And through the teaching of the great Scannerdanner I have learned sum shortcuts. I apologize if i have offended u or anyone with my comment..
HEY SCANNER DANNER CAN YOU USE THIS TOOL ON HONDA OR DO YOU NEED A SPESEL TOOL LET ME KNOW
Last added comment on common rail is the pressure in the system is 30,000psi!! they are right into the cylinder so that's probably why the voltage and windings within the injector are 100volts approx
I don't think you can, it would burn out the noid light bulb.
They may make a special type of bulb for your application. Wish I knew more about the diesels so I could advise you better than this
Dan I need your help. What are the two fat red wire leads that plug-in?. (Boshe injector Mercedes). On a 05 smart car CDI diesel..I've been trying to find out for 2 years now so I can diagnose why I have a no spray situation at the injectors. I don't want to just start poking around and blow the ECU. I've TRY to contact boshe in Germany, local Mercedes dealers.. injector service shops, etc... nobody can tell me...I'm guessing one is feed , the other is pulse((theres continuity between the two)) and gets ground through the body. But still not certain 🤔
Let's move this to my forum www.scannerdanner.com
It is free to join and we can definitely help you. I have 28k global members and hand picked moderators who've been with me for years and know my material inside and out and are there to help me help you guys. It is just too difficult to offer back and forth messages here on UA-cam with stuff like this and we also can't share pictures and images here like we can on the website. Hope to see you there!
What about ignition control module malfunction
Hey sir danner how are you. I just want to know what do you mean by injector on hold time ?? And thank you so much for your help. Greetings from Morocco 🙏🙏
How can I go about taking one of your classes you are awesome
Here www.scannerdanner.com/join-scannerdanner-premium.html
Thank you!
Hey Gang,
I just swapped out the four original Multec I injectors on my '94 Saturn SL2 (238K miles). It was the first time I ever removed a fuel rail and injectors. So it was a learn as I go project.I replaced the fuel pressure regulator as well, with the a AC-Delco unit, since it was original with 238K miles. The FPR didn't owe me anything, right?. I don't have a scanner. I do have a Fluke 87-V with basic leads, 'noid and a test light.
Upon start up I found cylinder 4 to be “dead”. I pulled out the plug lead and no RPM change. As I had new plug wires I swapped out the old ones (the old wires were due), and Scotch Brite cleaned the coil terminals. I bought a noid light kit and found that the #4 injector pig tail had a steady light, not flashing, as compared to cylinders 1-3. I DID NOT realize the significance of this steady light at the time. I got an RMA from the vendor and got another injector shipped.
Put in the injector and no joy. It was then I found this video and realized I might have a short to ground. I think my situation is the #3 bullet point.
As I've moved the wiring harness around for the fuel rail, MAP sensor, and TPS, I pondered whether I cracked some old insulation and created said short to ground. With KOEO I pulled the plug from PCM (plug port B-16 solid green for negative side of the injector #4 circuit), with the battery connected I affixed my test light to the positive battery terminal and the (-) side of th #4's pigtail. No light. I'm assuming therefore the negative side of the circuit is NOT shorted to ground, but I have a bad computer. When the engine runs I get the thick cloud of white smoke out back, so I know the injector is continuously on, and I hear no clicking from the injector via the screwdriver to the ear.
I have a reman'd unit offered to me for $80, via E-bay from a credible local vendor. But before I buy it I'm wondering if anyone has some thoughts. Paul, you out there?
Any help appreciated.
I always try to answer those who have clearly done there homework. Nice job so far! So you pulled the one single injector control wire from the PCM connector correct? Then you connected test light to b+ and touched the control wire harness side and it was not lit?
ScannerDanner Premium Sorry, I pulled the whole multi-plug out of the PCM. Then with battery connected I attached the test light to the + battery terminal, and the light's probe to the green ( - ) side of the #4's pigtail. My car is a Saturn SL2 1994 DOHC. I think it may have that ASD relay, but I'm not sure. Oh yeah, thanks for the awesome help and advice you do here.
Another edit: According to my Chilton book the plug port is B-16, but the Haynes book says D-16. Go figure.
ScannerDanner Premium Addendum: I pulled the entire plug out of the PCM. Then I connected the test light to B+ and to the - side wire harness of #4 I got no light. Sorry, I forgot to include that.
I also forgot to mention that I put a screwdriver to my ear and heard clicking for injectors 1-3, but nothing on #4.
I suppose another question I have, if the PCM indeed packed it in, is why it did so when I changed the injectors. When did I do somewhere to cause it? I had trouble removing the #4 plug, it was stuck, and the spring retaining clip was worn out. I broke the plug getting it off, and I wonder if shorted the circuit. Maybe I did. I have a spare pigtail on the circuit at the moment, just wire nutted, but I have to trim off the excess slack and solder/shrinktube it on permanently once I get the car roadworthy again.
RandallFlaggNY
did you see this one? ua-cam.com/video/jsl531-6q-A/v-deo.html
what you have sounds like a shorted PCM driver but watch this video to be sure
What about a misfire on two cylinders that are next to eachother that started incredibly suddenly? (Drove to go into restaurant to pick up food truck was fine. not even 2 minutes later back out to my truck and it's missing) Check Engine light flashes on the freeway sometimes but its always missing. Scan tool live data counts misfires on #2 and #4 on my 98 Chevy K1500 5.7. Fuel pressure was strong 60 psi. Compression was about equal to known good cylinders. (although I tested when engine was cold.)
I have this exact situation going on! I had white smoke that smelled like raw fuel injector #6 stuck wide open I shot the parts cannon at it...new plugs, wires , coil, injector, pvc even replaced the fuel pump....The noid light would light up. One day it just started running fine again, and now fast forward a year...I’m getting same cylinder misfire on #6 cylinder, but no more white smoke instead now noid is NOT working.. I’m getting 14 volts on feed side and 0 volts on the control wire... I did what you said and followed wire to computer and it’s saying 0 volts, however I can’t go any further the wires go up down and around the tight area under the battery box 09 Escalade hybrid .... does this wire go to fuse box? I believe it’s a shorted wire because it would only act up after it rained a few days...
14 and 0 and no white smoke? Your injector winding is open
Thanks for the prompt response! I’m gonna chase this wire down once and for all! 👍🏻
Remember, if that control wire is shorted to ground, that injector will be spraying fuel constantly! And you will absolutely have white smoke pouring out if the tailpipe
ScannerDanner that’s what it was doing a year ago and all symptoms went away and all of a sudden one rainy hot muggy midwestern day it came back in same #6 cylinder, however now instead of stuck open spraying fuel it it’s not clicking at all... I can feel the injector not clicking inside like the rest. I swap with cylinder #4 and it starts working. I’m thinking there was a corroded or shorted wire that finally snapped or something. when it used to act up I could tug on the harness and make it fix itself, but that won’t work anymore ...another indication it’s most like a broken or corroded wire or a loose connection.
@@vunit8213 I understand what it was doing before and there is no question you have a harness issue that was never fixed, however, if you have 14v on the feed and 0v on the control, measured right at the injector and you are sure the injector is not energized, there is only one cause for that, an open in the injector winding. You said when you switch it to another cylinder that the injector starts working? So when #6 is moved to #4, the #6 injector works?
A corroded wire that would lead to an open circuit, you would read battery voltage on both the feed and control wires when measured at the injector, but 0v at the computer.
scanner danner let me ask a question. my brother has an 01 4x4 silvarado. 1 whole side is getting pulse by ground but is only getting 1.8 volts on positive and it needs 14. I have checked the relay and notice 14 on one side 1.8 on another and 12 on another. I have tested a good 99 sierra and know for a fact 3/4 prongs on the asd relay will have 14 volts. MY question is where would the 1.8 come from originally that goes from the relay to the positive injectors on all of the passenger side. also*** the other side of the engine all have 14 volts when running on the positive side of the inj. if this makes sense please answer I think its coming from fuel pump module but am no expert. would love help
in a nut shell. on a good running same year truck. i know there is negative power pulse fluctuation, also I know there is 14 volts on all positive side of all injectors. on the bad running truck I have 14 volts on all inj on driver side and only 1.8 on all positive side inj from the passenger side. also I know from a good truck that 3/4 prongs on the asd fuel relay will have 14 volts when running. the bad truck only has (2) sides with 14 and a 1.8 that matches the failed passenger side. so where would the 1.8 volts come from. does it come from the fuel pump module or comp?
actually I saw a noid light that flashes but the injector is totally fine! its just a intermittent problem with the connector...
5.7 hemi code p0305 I changed the coil spark plug and swapped injector with a good one same code!! I also did a compression test 220psi!! Know what please help me!!! The engine shakes lightly but when going up an incline or giving it heavy gas it goes into a heavy Shake an engine light flash
I have code p0208 #8 injector circuit an p0308 #8 misfire..... while car running pulled injector 8 connector off an there no change in idle sound, Pulled #6 an there was a change in idle sound.... Put a noid light on 8 an no light....loosing my mind with this
Sir, I have one doubts why there is 3V on one side of fuel injector and not 12V in my i20 2011. There are no issues in my i20. Just curious to know whether it should be 3V or 12V?
With engine off and key at ON position, the connector harness is connected to the fuel injector.
Now, one end of multimeter is connected to ground and other end to one side of the fuel injector. The multimeter shows 12V, and other side of the connector shows 3V. Is this 3V supposed to be 12V and dropped to about 0V only when injector is switched on. Please note the injector is a computer controlled ground side switch.
Same result for the remaining 3 injectors. I'm really surprised why it's showing 3V rather than 12V on a ground side switch.
Do both injector wires go to the ECM? (GDI system)?
@@ScannerDanner yes both go to the ecm. The injector seems to be a ground side switch.
With connector still plugged, one side read 12v and other side read 3v with engine off and key at on position.
@@tnamen1307 then it is a GDI system and they are completely different in how they are controlled.
@@ScannerDanner it would be really great if you could make new videos explaining why there's 3v on one side in a computer controlled ground side switch circuit.
@@tnamen1307 I have videos on GDI injectors and how they are controlled.
Hi so I'm looking at your video and im having a problem with my 1988 2.8 Chevrolet s10 and the noid light is not coming on. The truck has spark can you please help.
Take a test light connected to battery positive with the key on and touch on and off the purple white wire coming from the ignition module. If the injectors fire, replace the module
ua-cam.com/users/edit?o=U&video_id=mxPdxGqRWvc
@fivefortyeye540i No problem and thank you. Imagine what you could do with my book:)
I have a 96 350c.i. 5.7 LT1 in my jeep. Runs perfectly at cold start, when I hit running temp at about 170°- 180° i start getting a flutter and bogs almost like bad iac she's rich smelling. My reader says multiple misfire and my iat is -38°.
Ok so after verifying no clicking at any injector on pass side ( tan wire ) and still no pulse at connectors at each injector. I went to PCM to pin 58 ( tan wire ) back probed pin and went to batt pos and still no pulse. Although back probing pin 59 ( White wire, bank that's working ) I get the pulse, confirming driver is sending signal out on that side. Also confirming driver for tan wire pass side not firing injectors is bad. I'ma call it a bad PCM driver and going to swap PCM out.
Let's make sure it is not some type of intentional shut-down of the injectors. The computer will do this when it recognizes a misfire to prevent the cat from melting down. The key in identifying this condition is to test for injector pulse immediately on start up. The computer will always try again on initial start up before shutting them back down.
@@ScannerDanner here is the post I made in the forum, shows pics ect. seems some bad wires pos to pulse wire crossed and shorted pcm. it is obd1 the other side works fine and is on a separate pulse wire. I did a batt disconnect, then reconnect and had someone turn key over as I was checking for pulse on the side in question. Just to make sure it wasn't an auto shut down. Then I went to pcm/ecm. Pulses on side that works pin 59 but not on the side that don't pin 58. Found a good used ecm for 35.00 so I'ma ( lol ) swap it because it's cheap enough and being obd1 and same MT/FED and part number as well as no programming because of age and type.
Your videos have helped me greatly with diagnosing this obd1 system. Let me know what you think after looking over the post in the forum linked below.
www.scannerdanner.com/forum/search.html?query=engine%20running%20on%20one%20side&searchdate=all&childforums=1&catids=4
Ad what is probable cause of bank 1 no power to injectors bank 2 is fine. I've trouble shot to be a bad brain?
It is becoming more and more difficult to answer questions here. I have 80,000 people asking me for help now. So I have created a forum to help you guys better. It is free to join and we can exchange pictures, wiring diagrams and waveforms if needed to help guide you through the process of troubleshooting your vehicle. Thank you so much! Hope to see you there.
Paul Danner (ScannerDanner)
www.scannerdanner.com/forum/post-your-repair-questions-here.html
👍👍👍
+scannerdanner I guess the moral of the story here, is it pays to know your circuit designs. Diagnosing can be simple when you have the road map in front of you!
Some of these engines you can't even get to the injector unless you take half the engine apart.
Arthur Rodesiler that's exactly my issue with my '95 200sx SE-R. such a pain in the ass
On a throttle body with obd-1 with just injectors a noid light helps....on obd-2 you really need a scanner to find it. Much faster....take it to a dealer as most new cars you are pretty much never gona find the problem for the diy.
for some reason I'm unable to view the video.
Try it again, you should be good.
i dont use noid lights anymore as i just bought a wecprobe