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My miss fire just started and is sporadic. P0204 jeep liberty. At times I turn on the vehicle it acts normal and other times on start is misfires cylinder 4. I swapped the coils and spark plugs to see if it would follow and it doesn't. Now I believe it comes down to the injector acting sporadic or from the the electrical plug. Any thoughts?
My Jeep is a "crank, no start" and I needed a refresher on how to use a Noid light. I learned more than I was looking for by watching this video. Thanks Dave.
I've looked at a lot of videos about misfire diagnosis and using the Power Probe and this is by far the best that I've seen. Clear, simple instructions. You've taken out some of the mystery and confusion that others gave.
Absolutely loved the bonus footage showing the leak down test. I was wondering what the problem was up until that point. Thanks for taking the time and trouble of making this excellent, nay, Superior video, and sharing your skill and knowledge with us! Thanks again, David
I'm not sure why it took me so long to find your channel, you earned a sub today for sure. We have many similarities, not least of which is our addiction to quality automotive tools. What I really like about your channel is the way you explain how these systems work first, which gives a reliable compass to look for solutions. It was fun to see you use PP4 for the fuel injector. Eric O sent me one of those but I've never used the fuel injector feature. Once I see the test light flashing, I tend to follow the ScannerDanner blueprint of looking at current waveforms. There are lots of right ways to get to the answer.
Great video and information. You got me towards the end. I was thinking dude what do you check next if the darn injector is getting power and fuel. Then right before I was about to type you the ?, you jumped in with the bonus video of checking the compression and leak down. After that I was saying out loud in my garage to the point my neighbor looked over as I was yelling this guy is awesome and very knowledgeable and lest us lay people know each step to achieve results. I am working on a 2012 dodge caravan with the 3.6 pentastar engine but it looks like your steps will work. I replaced a ton of stuff that requires relearn but I can’t get the van to barely run. I don’t think bank 2 cylinders are firing. I am going to start at your step 1. Thank you Sir for helping out us little people who can’t afford to send the vehicle to a shop.
stumbled across this. you sir are THE MAN!. I have been fighting a no start on a Harley for weeks. It started off with a broken wire going to the throttle body then turned into a mess.
@@BigDog50001 will not the reverse voltage spike flows back to the power feed side and cause short circuit?? Analogy to a diode in a relay, is similar diode or capacitor necessary to absorb the reverse spike and protect the circuit and the solenoid itself?? Please kindly elaborate a bit more.
This is one of the best vid it explains very well n easy to understand wht need to be done if you myb only hv test light or noid light thnks for the video u gained a follower n a subscriber
Your videos are really very informative. Lots of info and professionally explained. Like the way you stay on topic and explain what is going on. Excellent
Thank you for the video. I am trying to diagnose a Misfire cylinder 1 P301 hyundai v6. I am at the fuel diagnosis stage. My suspicion is not ignition (spark) based on maintenance and tests of ignition. Timing seems not an issue as cylinder specific on this DOHC timing would cause entire bank issues (misfires P300). Assuming that not seeing the pintile spray pattern through these tests is an issue however your stating that the Power probe 4 showing more data compared to a known good injector shows simpler pulse pattern thus not injector issue.
Great video, really appreciate all the explanation. Probably a dumb question: how do you hook up the tester probe? Looks like you jammed the probe down into the connector ground from the back while it’s plugged into the injector? (I guess that’s why they call it back probe?)
Yes I probed it from the back where the wire is crimped to the connector. The probes I use are sharp like a needle which makes it easier to back probe. Thanks for the comment!
I just subscribed your channel. Thanks for sharing your video. I just have a question for the power probe. Where do you connect the power probe to test the injector? Is it in the connector or to the injector directly? And also the NOID will it work to mercedes benz injectors connector
Great video So if i back probe plugged in injector with my power probe 4 and i get data like rest of cylinders does that mean injector is good ? Or just circuit system to injector is good
I have kyzee power probe,. Can i use this on ac voltage or dc voltage? I have frequency on the tool? Any reply appreciated cheers from Australia subbed and liked 👍 ❤
Great video, thank you. My 1994 Dodge Dakota 5.2 is driving and running, but throwing an intermittent code for the injector output signal circuit. Even when running fine, I get power (test light bright on all injectors power side), but no ground (no pulsating light to ground side on any injector). Do you know what may cause this... And how is the truck running with no ground to the injectors??
Be sure to subscribe for more tool and car repair videos! ua-cam.com/users/BigDog50001 twitter.com/BigDog50001 instagram.com/bigdog50001/ Disclosure: This channel earns a small commission using some of these links - at no additional cost to you. The Big Dog 50001 Automotive Channel Store can be found here: www.amazon.com/shop/bigdog50001automotive
Great video....What happens if we have 12 volt constants but we don't have the pulses from ECM....we already check integrity of cable from injector conector to ECM end.....the diagnostic gave to be ECM replace it or can I do something else?
I can't see what you have done as far as testing and I don't know what model or vehicle you are working on, but what you are describing is the transistor/driver for the injector inside the PCM not working. Some vehicles/models will intentionally shut down an injector when it detects an issue so clearing the code, cycling the key and then immediately testing with a test light/noid light would be my next step (but even that is not fool proof as certain vehicles can detect the incorrect current flow/resistance of a test light). If the PCM is intentionally shutting it down then the test light will flash briefly and then the PCM will most likely shut it off again very quickly. Also be aware that if the driver in the PCM was damaged, I would try and locate the reason the driver went bad before installing a new PCM (bad wiring/shorted injector etc). Thank you for the comment!
That was a GREAT explanation, thank you!!! I'm doing the same thing on my 2009 Escape with the 2.5L. Cylinder 1 is misfiring. Injector, coil, and plug are all good. Compression is good but I'm going to do a leak down test anyway. Have you ever had any experience with good compression but a failed keak down? Thank you again!!!
@@BigDog50001 yeah sucks if they would have brought it in when the engine started to tick would have been a 1 hr labor and new valve cover gasket to make a easy fix. But sometimes people don't understand.. but thanks for the reply back
Hi there this is a good diagnoatic video. One question when you used the power probe to check the connection i beilive you said you back probed the ground right? If so how could you tell there was good voltage at the same time by only probing the ground? Thanks
Voltage does not drop until there is current flow (Ohm's Law). You will see 12V because it coming in on the other wire and is going through the coil winding inside the fuel injector and stays that way until it is turned on (creates current flow). You will not see 12V if the coil inside the injector is broken. Thanks for the comment!
Okay.. Just confused by what you said at the end.. Plugged in it was running rich from the injector dumping fuel, unplugged it evened out, so that means the injector is working properly? I don't understand. Would that not indicate that the injector is leaking? Not that it is in good condition?...
Don't get too hung up on that one test, it is just a quick and dirty way to see if injector is spraying fuel . If the fuel trims change when it is connected/disconnected then it at least gives an indication that something is happening (in this case spraying fuel when connected and not spraying fuel when disconnected). We knew it was a dead misfire, happening all the time, so this was another way to give some direction (should we go left or should we go right) and it helped me steer away from fuel injector and look somewhere else.
I've been having this flooding issue on my 2004 BMW M3, cylinder 6 at first was floodying, throttle body was full of fuel and having misfire on that cylinder along w/ cylinder 5 and 4 having pending codes for misfires as well. At first we thought its just pre-cat o2 sensor since it was only happening after the car has warmed up but after switching pre-cat o2 sensor it started doing right off the bat, checked the values I am getting for pre-cat o2 sensor and it was good. that's when I found the fuel in the throttle body, plugs were changed, coils were changed and still happening and at one point the "flooding" went to cylinder 5 for a little bit then went back to cylinder 6. Checked compression ratio on cold engine (Since I didn't really want it to run misfiring like crazy dumping fuel in the cylinder). everything actually checked out, 10psi lower than minimum but it is to be expected on a cold engine compression check. injectors was sent out for testing/cleaning/rebuild and everything came back great there was no note of sticking injector in the report sheet that I got. what else could it be? I was thinking maybe either wiring harness or DME, how can I check if the harness is shorted out on the injector w/o turning on the car?
A test light should show if a control wire to the fuel injector is shorted to ground (on all the time). I would try and narrow it down to whether it is a rich condition due to inputs that the ECM uses to control fuel delivery (O2/MAF etc) or is it a symptom due to mechanical problem (faulty or shorted injectors/wiring/air flow issue etc). Long term and short term fuel trims using a scan tool are where I would start (is ECM adding fuel and creating a rich condition or taking it away trying to control a rich condition). Upstream and downstream oxygen sensor readings at different RPMs and engine loads are also something I use to diagnose (do sensors go rich/lean like they are supposed to and are they responding properly). Sometimes sensor/solenoids only act up at certain temps too. I would look for engine trouble codes too. I believe cylinders 4, 5 and 6 are next to each other on the vehicle, so I would look for things they may have in common that could effect them all. Also, if the alcohol content in the fuel is not correct, it can create fuel delivery issues but that would probably effect all cylinders.
@@BigDog50001 I tried using test light, clipped it on the power side of the battery and identified the ground cable on my injector harness and had someone crank the car while doing it, both cylinder that had the flooding problem was doing what they supposed to do, pulsing faintly. tested the power side clipped the test light on a ground and put the test light on the power side while the ignition is on and both got power. So far things I've done, New plugs and coils, New Pre-cat o2 sensor Injector rebuilt compression checked and passes checked injector harness w/ test light and passes. And cylinder 6 floods w/ fuel as if there were no spark. and sometimes it jumps to cylinder 5, codes that is out right now is multi misfire code and cylinder 6 misfire with two pending codes for cylinder 4 and 5. Thanks for your time helping me figure this out.
I'm working on a 1995 Corvette ,new injectors ,44 lbs fuel pressure, noid lights flashing but will not spray fuel. If I use a 9v battery and jumper wire to injector ,it clicks and sprays. I have full voltage to injectors power wire. Would you have any ideas? Driving me crazy , also if I spray fuel into tb , runs great till fuel of gone. Nice video. HELP please
Hi there. I just subscribed to your channel and was watching this video. I really like the way you make things very easy and simple to understand. However, one thing I wish you would have done in this video and that is, to explain the 'back probing' a little more - especially for us newbies to automotive work. Also, a more close up view would have been great while you were back probing. It was kind of hard for me to see exactly where you were putting the probe when you tested the 2nd injector. Also, did you reconnect the 1st injector before disconnecting the 2nd injector to test? Otherwise, great video in explaining the (3) test devices.
Welcome! Each video I try to get better! As far as the back probe is concerned, I just took the back probe that I showed at 8:00 minutes and stuck it right next to the control wire (ground) where the wire enters the connector on the fuel injector (it is touching the wire inside). As far as testing with the back probes using the PowerProbe, I back probed and tested both fuel injectors (#2 and #1 cylinders) the same way. When testing with the PowerProbe (unlike the test light and noid lights), I left the fuel injector that I was testing plugged in, otherwise it will not test correctly. I unplugged the #2 cylinder at 10:55 minutes (the one with the misfire) AFTER I was done testing it because I did not want fuel being dumped into a cylinder that is not working.
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This channel earns a small commission using some of these links - at no additional cost to you.
PowerProbe IV: amzn.to/2zQqcFL
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OTC Leak Down Tester: amzn.to/2NMtIcf
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My miss fire just started and is sporadic. P0204 jeep liberty. At times I turn on the vehicle it acts normal and other times on start is misfires cylinder 4. I swapped the coils and spark plugs to see if it would follow and it doesn't. Now I believe it comes down to the injector acting sporadic or from the the electrical plug. Any thoughts?
V.
I watched so many videos just to get this one answer.. Thank you..
Thanks for the bonus footage! I thought you were gonna leave us hanging. It would've been like watching a movie and not showing us the ending.
The kind of explanation I never saw in the period of 25 years, it's awesome .The tools and way you trouble shooting fantastic and perfect.
I appreciate the comment, thanks!
My Jeep is a "crank, no start" and I needed a refresher on how to use a Noid light. I learned more than I was looking for by watching this video. Thanks Dave.
I've looked at a lot of videos about misfire diagnosis and using the Power Probe and this is by far the best that I've seen. Clear, simple instructions. You've taken out some of the mystery and confusion that others gave.
I appreciate the comment, thank you!
Excellent Video, your ability to make things easy to understand for an amateur mechanic is unmatched. Please keep them coming!!
Thank you, I appreciate the comment!
Absolutely loved the bonus footage showing the leak down test. I was wondering what the problem was up until that point. Thanks for taking the time and trouble of making this excellent, nay, Superior video, and sharing your skill and knowledge with us! Thanks again, David
I appreciate the comment, thank you!
Thank you for giving us the final diagnosis - not having it would have been a "tough itch to scratch."
I'm not sure why it took me so long to find your channel, you earned a sub today for sure. We have many similarities, not least of which is our addiction to quality automotive tools. What I really like about your channel is the way you explain how these systems work first, which gives a reliable compass to look for solutions. It was fun to see you use PP4 for the fuel injector. Eric O sent me one of those but I've never used the fuel injector feature. Once I see the test light flashing, I tend to follow the ScannerDanner blueprint of looking at current waveforms. There are lots of right ways to get to the answer.
Great video and information. You got me towards the end. I was thinking dude what do you check next if the darn injector is getting power and fuel. Then right before I was about to type you the ?, you jumped in with the bonus video of checking the compression and leak down. After that I was saying out loud in my garage to the point my neighbor looked over as I was yelling this guy is awesome and very knowledgeable and lest us lay people know each step to achieve results. I am working on a 2012 dodge caravan with the 3.6 pentastar engine but it looks like your steps will work. I replaced a ton of stuff that requires relearn but I can’t get the van to barely run. I don’t think bank 2 cylinders are firing. I am going to start at your step 1. Thank you Sir for helping out us little people who can’t afford to send the vehicle to a shop.
Thank you, I appreciate the comment!
stumbled across this. you sir are THE MAN!. I have been fighting a no start on a Harley for weeks. It started off with a broken wire going to the throttle body then turned into a mess.
I appreciate the comment, thank you!
What was the problem ?
Calling someone out within the first second of a video; now thats a bold move... I LIKE IT! :)
lol
Damn!
You just doubled my knowledge on computer controlled injection system!
I have a 93 accord! Yours looks almost exactly like mine!
Great video!
👍
Found this video while searching for noid lights. Thanks for this very clear explanation! Subscribed right away to your channel.
Thanks for the comment and welcome!
The bonus made the difference between this video and the others. Excellent job .
Really liked the video and explanations being simple and easy to understand. Thank you.
Thank you, I appreciate the comment!
@@BigDog50001 will not the reverse voltage spike flows back to the power feed side and cause short circuit?? Analogy to a diode in a relay, is similar diode or capacitor necessary to absorb the reverse spike and protect the circuit and the solenoid itself?? Please kindly elaborate a bit more.
Excellent explanation of how a fuel injector fires; I did not know that. Thank you.
You've got yourself a new subscriber my friend 🎉
Welcome!
Great video, really most helpful one out there on injectors. Thanks!
Thanks!
Where have this guy been all my life great stuff! Just subbed
lol, thank you for the comment and welcome!
Dear sir,ive just come across this video.
A most exellent video.very clear and precise and methodical.
Keep up the great videos.steve from the uk.
Thanks 👍!
Enjoyed the video. Really glad you showed the bonus showing the problem. Thank you for doing the video.
Thank you for the comment, I really appreciate it!
Super explanation 👌. Thanks for the time to put it together and sharing.
You bet 👍!
Love that Bonus footage. that told the tail.
Thank you for the comment!
This is one of the best vid it explains very well n easy to understand wht need to be done if you myb only hv test light or noid light thnks for the video u gained a follower n a subscriber
Thanks and welcome!
Nice work! Of course the owner is sick to hear the news! Thanks for the video!
👍
Very nice video. Thank you very much. I wish there was a scope out there that wasn't so expensive that would show the fuel injector opening.
Thank you for the comment. Here is a scope I have that is not too much money: goo.gl/FU9AAA
Thank you, I'm faimilar with diesels but petrols are a completely different headache. I enjoy the knowledge for troubleshooting :)
Thanks for the comment!
Another EXCELLENT instruction video - YES , I did GREATLY ENJOY . You are indeed and EXCELLENT Technician. Many thanks for sharing 😊👍👍👍✌️✌️✌️
Thank you, I appreciate the comment!
Your videos are really very informative. Lots of info and professionally explained. Like the way you stay on topic and explain what is going on. Excellent
Thank you!
Excellent troubleshooting
Thanks 👍!
I infact did enjoy the bonus footage
Awesome, thanks 👍!
Great tutorial video, from beginning to the end............... Thanks!
Good bonus with scope
The best yet. Keep em coming
Nice and easy, good demo.
Best video on injectors!
Thanks!
This must be as good an instructional video for any automotive troubleshooting as I have ever seen. Great job,
Big Dog50001 Automotive
I appreciate the comment, thank you!
Thank you for the video. I am trying to diagnose a Misfire cylinder 1 P301 hyundai v6. I am at the fuel diagnosis stage. My suspicion is not ignition (spark) based on maintenance and tests of ignition. Timing seems not an issue as cylinder specific on this DOHC timing would cause entire bank issues (misfires P300). Assuming that not seeing the pintile spray pattern through these tests is an issue however your stating that the Power probe 4 showing more data compared to a known good injector shows simpler pulse pattern thus not injector issue.
Excellent display and knowledge of work!
Excellent and thorough
Thanks for the comment 👍!
Keep them coming mate the info is good .
I appreciate the comment, thanks!
Im a stingy sob. U direct to point and thorough.
Thank you so much. Best video out there on the topic!
Really excellent, clear and very usefull. Well done sir.
really great diagnosing!
Thanks 👍!
Excellent!! Great work, very helpful, to the point!, keep it up the good work!!
Excellent presentation.
just got a power probe 4 love it
I like mine, I think they are a good little tool to have in the tool box. Thanks for the input!
Great video. Keep it up
You're a great teacher!
Thank you for Brilliant video, one question please, can I carry out same test using power probe 4 for testing Diesel injector?
Excellent video, thanks for sharing. Cheers
Thank you for the comment!
Great video, really appreciate all the explanation. Probably a dumb question: how do you hook up the tester probe? Looks like you jammed the probe down into the connector ground from the back while it’s plugged into the injector? (I guess that’s why they call it back probe?)
Yes I probed it from the back where the wire is crimped to the connector. The probes I use are sharp like a needle which makes it easier to back probe. Thanks for the comment!
A Great job, very informative. Off to price up some kit. Thank you.
Thanks!
This was a great video. I need to get a power probe...just haven't pulled the trigger on it yet.
Thanks! It is a nice tool to have, I definitely use mine a lot.
Thanks for the excellent demonstration. This was very good.
Rob's Wrenches Thank you!
I just subscribed your channel. Thanks for sharing your video. I just have a question for the power probe. Where do you connect the power probe to test the injector? Is it in the connector or to the injector directly? And also the NOID will it work to mercedes benz injectors connector
Great video So if i back probe plugged in injector with my power probe 4 and i get data like rest of cylinders does that mean injector is good ? Or just circuit system to injector is good
Thank you sir, very well done, very informative .
I appreciate the comment, thanks!
I have kyzee power probe,. Can i use this on ac voltage or dc voltage? I have frequency on the tool? Any reply appreciated cheers from Australia subbed and liked 👍 ❤
I use a scope often but I didn't know about the pintle hump on the waveform; thanks.
Thank you for the comment!
Great video, thank you. My 1994 Dodge Dakota 5.2 is driving and running, but throwing an intermittent code for the injector output signal circuit. Even when running fine, I get power (test light bright on all injectors power side), but no ground (no pulsating light to ground side on any injector). Do you know what may cause this... And how is the truck running with no ground to the injectors??
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Thank you very much! Easy and clear explanation. I Like it in this way.
Thanks for the comment!
nice video, refreshed my memory. good will always over come the bad. thats for the people that gave a thumbs down.
I appreciate the comment, thank you!
This is quality content. Keep it up.
Thanks 👍!
Love my power probe 4 is a great tool
Great, clear video. Thank You
I appreciate the comment, thanks!
I always watch your videos and I love them, all of them, but on index 2:49... do you expect us to buy that equipment?
I just love this site brilliant.
THANKS..
👍
Great video!!!! was the intake valve lash tight holding the valve open? or was it burnt?
Both, thanks!
I'm glad you explained the "no start" part at about 7:15
Edit: but what about using the power probe? Same thing?
Subscribed. Great video thanks. Hello from Australia
Great video....What happens if we have 12 volt constants but we don't have the pulses from ECM....we already check integrity of cable from injector conector to ECM end.....the diagnostic gave to be ECM replace it or can I do something else?
I can't see what you have done as far as testing and I don't know what model or vehicle you are working on, but what you are describing is the transistor/driver for the injector inside the PCM not working. Some vehicles/models will intentionally shut down an injector when it detects an issue so clearing the code, cycling the key and then immediately testing with a test light/noid light would be my next step (but even that is not fool proof as certain vehicles can detect the incorrect current flow/resistance of a test light).
If the PCM is intentionally shutting it down then the test light will flash briefly and then the PCM will most likely shut it off again very quickly. Also be aware that if the driver in the PCM was damaged, I would try and locate the reason the driver went bad before installing a new PCM (bad wiring/shorted injector etc). Thank you for the comment!
Good video
I have watched some of your vids too, great content! Thanks for the comment!
On the snap on kit you have shown us the chart/graph. What is this graph called exactly? Injector graph?
That was a GREAT explanation, thank you!!! I'm doing the same thing on my 2009 Escape with the 2.5L. Cylinder 1 is misfiring. Injector, coil, and plug are all good. Compression is good but I'm going to do a leak down test anyway. Have you ever had any experience with good compression but a failed keak down? Thank you again!!!
Thanks for the comment 👍!
Thankyou. Do more on test light
👍
Thanks, helped a lot !!
Great video did you see if you can adjust the valve first before going the distance of pulling the head
No, not on this one due to evidence of overheating.
@@BigDog50001 yeah sucks if they would have brought it in when the engine started to tick would have been a 1 hr labor and new valve cover gasket to make a easy fix. But sometimes people don't understand.. but thanks for the reply back
Hi there this is a good diagnoatic video. One question when you used the power probe to check the connection i beilive you said you back probed the ground right? If so how could you tell there was good voltage at the same time by only probing the ground? Thanks
Voltage does not drop until there is current flow (Ohm's Law). You will see 12V because it coming in on the other wire and is going through the coil winding inside the fuel injector and stays that way until it is turned on (creates current flow). You will not see 12V if the coil inside the injector is broken. Thanks for the comment!
Clear and concise , well explained.
Thanks!
Amazing tutorial!
Thanks 👍!
Okay.. Just confused by what you said at the end.. Plugged in it was running rich from the injector dumping fuel, unplugged it evened out, so that means the injector is working properly? I don't understand. Would that not indicate that the injector is leaking? Not that it is in good condition?...
Don't get too hung up on that one test, it is just a quick and dirty way to see if injector is spraying fuel . If the fuel trims change when it is connected/disconnected then it at least gives an indication that something is happening (in this case spraying fuel when connected and not spraying fuel when disconnected). We knew it was a dead misfire, happening all the time, so this was another way to give some direction (should we go left or should we go right) and it helped me steer away from fuel injector and look somewhere else.
VERY GOOD EXPLANATIONS.
Thanks!
Very helpful video. Wanna more!
lol thanks!
I've been having this flooding issue on my 2004 BMW M3, cylinder 6 at first was floodying, throttle body was full of fuel and having misfire on that cylinder along w/ cylinder 5 and 4 having pending codes for misfires as well.
At first we thought its just pre-cat o2 sensor since it was only happening after the car has warmed up but after switching pre-cat o2 sensor it started doing right off the bat, checked the values I am getting for pre-cat o2 sensor and it was good.
that's when I found the fuel in the throttle body, plugs were changed, coils were changed and still happening and at one point the "flooding" went to cylinder 5 for a little bit then went back to cylinder 6.
Checked compression ratio on cold engine (Since I didn't really want it to run misfiring like crazy dumping fuel in the cylinder). everything actually checked out, 10psi lower than minimum but it is to be expected on a cold engine compression check.
injectors was sent out for testing/cleaning/rebuild and everything came back great there was no note of sticking injector in the report sheet that I got.
what else could it be? I was thinking maybe either wiring harness or DME, how can I check if the harness is shorted out on the injector w/o turning on the car?
A test light should show if a control wire to the fuel injector is shorted to ground (on all the time). I would try and narrow it down to whether it is a rich condition due to inputs that the ECM uses to control fuel delivery (O2/MAF etc) or is it a symptom due to mechanical problem (faulty or shorted injectors/wiring/air flow issue etc).
Long term and short term fuel trims using a scan tool are where I would start (is ECM adding fuel and creating a rich condition or taking it away trying to control a rich condition). Upstream and downstream oxygen sensor readings at different RPMs and engine loads are also something I use to diagnose (do sensors go rich/lean like they are supposed to and are they responding properly). Sometimes sensor/solenoids only act up at certain temps too.
I would look for engine trouble codes too. I believe cylinders 4, 5 and 6 are next to each other on the vehicle, so I would look for things they may have in common that could effect them all. Also, if the alcohol content in the fuel is not correct, it can create fuel delivery issues but that would probably effect all cylinders.
@@BigDog50001 I tried using test light, clipped it on the power side of the battery and identified the ground cable on my injector harness and had someone crank the car while doing it, both cylinder that had the flooding problem was doing what they supposed to do, pulsing faintly. tested the power side clipped the test light on a ground and put the test light on the power side while the ignition is on and both got power.
So far things I've done,
New plugs and coils,
New Pre-cat o2 sensor
Injector rebuilt
compression checked and passes
checked injector harness w/ test light and passes.
And cylinder 6 floods w/ fuel as if there were no spark. and sometimes it jumps to cylinder 5, codes that is out right now is multi misfire code and cylinder 6 misfire with two pending codes for cylinder 4 and 5.
Thanks for your time helping me figure this out.
Very good video and explanation.
Thanks!
Excellent
Thanks!
I'm working on a 1995 Corvette ,new injectors ,44 lbs fuel pressure, noid lights flashing but will not spray fuel. If I use a 9v battery and jumper wire to injector ,it clicks and sprays. I have full voltage to injectors power wire. Would you have any ideas? Driving me crazy , also if I spray fuel into tb , runs great till fuel of gone. Nice video. HELP please
Super indicative video, keep it up bro,,
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Great video 👍
Hi there. I just subscribed to your channel and was watching this video. I really like the way you make things very easy and simple to understand. However, one thing I wish you would have done in this video and that is, to explain the 'back probing' a little more - especially for us newbies to automotive work. Also, a more close up view would have been great while you were back probing. It was kind of hard for me to see exactly where you were putting the probe when you tested the 2nd injector. Also, did you reconnect the 1st injector before disconnecting the 2nd injector to test? Otherwise, great video in explaining the (3) test devices.
Welcome! Each video I try to get better! As far as the back probe is concerned, I just took the back probe that I showed at 8:00 minutes and stuck it right next to the control wire (ground) where the wire enters the connector on the fuel injector (it is touching the wire inside). As far as testing with the back probes using the PowerProbe, I back probed and tested both fuel injectors (#2 and #1 cylinders) the same way.
When testing with the PowerProbe (unlike the test light and noid lights), I left the fuel injector that I was testing plugged in, otherwise it will not test correctly. I unplugged the #2 cylinder at 10:55 minutes (the one with the misfire) AFTER I was done testing it because I did not want fuel being dumped into a cylinder that is not working.
Thanks for the info
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Do you have to select power or ground on the probe, or it defaults to ground when you select the injector function?
Very good thank you.
I'm buying the Power Probe 4 Master kit this Friday...Hell to the yes.....$263.00 on Ebay.
A Power Probe is a nice addition to the tool box!
Well done!!
Thanks!
good comparison! and nice tools!
The Disgruntled Mechanic Thanks Mike!