Wow! The ohm meter for the win over the picoscope! Every tool has it's value and knowing witch one to use is priceless. Thanks for posting this video, it's worth its weight for sure!
New subscriber here thanks to Paul and Caleb Danner. I’m looking forward to binge watching all of your videos tonight so that I can get caught up on your content!
I notice that when the 65V shuts off; the #1 had 2 pulses of ringing. The #6 had only 1. I would not expect that to vary with injector on time. Don’t know if it’s significant. With the isolated input of the Pico, one channel’s leads can be connected across the injector so as to show the actual voltage response of the injector. Or a math channel could be set to show the composite waveform. I think it would be easier to spot differences that way. The same goes for looking at a CAN bus.
I'm curious if current (work being done) would have picked up anything useful vs voltage. As I see also had p300 misfire. Or maybe only would have shown up when it was bad enough to feel the misfire.👍
That's an interesting waveform, almost as thought the circuit is both power side and ground side switched. Is 65 volts a normal voltage for these? It seemed to go on for too long for it to be an inductive spike.
Nice diagnoses, and taking the time to share with us. I wanted to ask if you had build a math channel of channel A voltage divided by channel B current / you would have a resistance display channel which would have been nice to see a dynamic display of work being done. Just a thought and wanted to see your thoughts. thanks.
😄 Injectors.!! I'm just glad I'm not the only one that gets the multiple vehicle repeated problems. Mine usually show up in two's back to back or 3 within the same week. Lol Only good I see about it is...your mind set is already in that game to diag. Cheers Bro 😎👍🍻
Another excellent video! Really would information! reminds me of a 2011 QX56 with P0300 the dealer had recommended new engine harness, ECM, Injectors and one relay. I did what you just did in this video! Thank you for sharing!
I bet we missed all the fun of pulling that injector out. If you're lucky the others don't go bad after. I would replace the whole bank. Sometimes fixing these things costs a lot of money. Don't let it eat your time. GM injectors are not that good. Great job and nice equipment.
I wonder if you measured both voltage and current, and then using the math channel you could have divided the current into the voltage which would have given you a dynamic resistance reading on the scope.
@@autodiagyt Start playing with it, Pico math channels have a lot of diagnostic uses from plotting crank shaft frequency to finding intermittent parasitic drains. CTI Research & Development channel has a really good class on it. Agreed, Darren is pretty good as well. The Pico channel has some good stuff on math channels, so does Super Mario.
Man these GDI systems really don't seem very long term reliable... Plus are sooo much more expensive to repair for the customer! I usually reuse the fuel lines to avoid wasting resources and paying GM more money 💸😅
@@autodiagyt yeah I see that point of view for sure. Do you also replace all the combustion seals on every injector every time the rail is pulled? There is a chance of harming the good injectors every time those seals are removed and pressed on... Another reason I'm not a huge fan of GDI lol
Hello from Sand Mtn good video, good find using an oldie but a goodie the old ohms test, I have found that when I have one of these with a bad injector that after a little investigation I usually find the rail was taken off prior to the fault, you know as well as I do very easy to damage these during removal
It's weird how it kept changing. It started at 1.55M and then went to 1.45M and on your last test it was down to 1.37M.. The one other thing that I would have looked at closely is inside the connector of the injector. If it somehow leaked some gunk down into the connector, it could simply have a little build up or corrosion bridge from one pin to the next on your injector connector-- where you may have been able to just clean it out and then maybe the injector would test fine after that. (it's possible :) Otherwise, 1.55M ohms on a 12v can only pull 7.72 microamps, Which means there would be almost no voltage drop across it; so it's so incredibly small that I'm actually surprised that the computer could sense it.. Even your scope likely only has 10M ohms per volt of resistance, while measuring voltages.. And our scope/ DVOM's are essentially considered imperceivable to the circuit-- and this short was beginning to approach that same realm.... The fact that it was changing every time you tested it again, makes me think that it must have changed so drastically, possibly after heating up, that it spiked the driver enough to trip the code.. I think it was just the fact that it was only 1.5 ohms rather than 1.1 ohms like all the others, so it was actually not pulling enough current, and that's what the computer was sensing, and not that Mohm short. It would have been really cool to see you cut open the injector with a cutting wheel. Particularly in a way that we could see behind the connector.
@@autodiagyt Right on.. my mind is still just curious as to what is actually happening. lol.. I wish you could cut it open; maybe something is obvious. I bet the problem is just right there at the pins, on the inside.
PCM probably does a circuit test and gets pulled down and thats how it knows there is a circuit issue. Though, to protect itself it should not fire that injector because it would know there is a short which would damage internal transistor. Perhaps some engineer can help us explain what tests the PCM does during key on.
I am only guessing but if I wanted to see something in the scope trace then I would overlay #1 & #6, not #1 & #1 or #6 & #6. The added resistance may show up in a longer trace going back towards 0 after the injector was done firing?? Thank for all the great videos, in the process of watching all of them and all future as a SUBr.
Checking injectors cold and hot is a requirement, they are all hot so all measurements hot should be in the same neighborhood, as you mentioned, you will not be looking for the cold spec while hot. Showing the after the fix measurements is also a LIKE to see from your viewers according to the feedback on many other auto repair videos.
I was going to ask why you didn't test both wires for a partial short to ground. At first I thought maybe the pcm shares a 12 volt internal for all 8 injectors (like it does for the 5 volt) and there was no need because all 8 would be effected . Then you tested it thought gone, Awesome job.
Interesting, I wonder if the scope would have shown anything if you had driven it under load like the last one but then again you didn't have to since the ohm check showed an obvious fault in the circuit.
That an awesome diagnostic.I'm having trouble with my injectors too with my 2021 chevy silverado with a code of P02EF,P2B09 AND P2B95.Hope you can help me out.More power...
2015 silverado 5.3 P0205 misfire I replaced the #5 injector but still having the same issue and the same code,,, Tested the injectors for resistance at the main connection by the fuse box (1,3,5 all on the same fuel rail) have readings all others are reading 0L please help! thx
I'm having same issue with my 2014. New pcm . Changed number 6 injector twice. Even ran a new wire from pcm to number 6 cylinder and still getting the PO206 code. But all 8 injector wires only say 6 to 8 volts... and my injectors ohm out to only 00.6. I'm lost
1.4 megohms isnt much of a short for the computer to be complaining about. GM made a bunch of injectors for tpi engines in the 80s and 90s that would get shorts in the coil windings that might only show up when they were hot. The car would run for about 30 minutes on the highway and shut-off. The driver transistors would be overworked, from the kow resistance coils, and go into thermal cutoff, ending fueling abruptly. No codes, no start for about 45 minutes and it would fire right up. I thought it was ignition at first. Yay injectors.
SUBSTANTIAL Automotive Diagnostics Programming My teacher Automotive Diagnostics Programming Wow can't believe that Thanks for sharing what you know with us Maybe wrong settings on your PicoScope Thank you enjoy your holiday with all your family around you SUBSTANTIAL Automotive Diagnostics Programming From Nick Ayivor from London England UK 🇬🇧
Wow! The ohm meter for the win over the picoscope! Every tool has it's value and knowing witch one to use is priceless. Thanks for posting this video, it's worth its weight for sure!
Amp clamp with scope?
Great Video and analysis, Thanks for sharing. I have done few of the high pressure fuel injector diagnosis. Your video certainly helps.
New subscriber here thanks to Paul and Caleb Danner. I’m looking forward to binge watching all of your videos tonight so that I can get caught up on your content!
I've seen every video on this channel. Totally worthy.
Sent over from Danner. Video was excellent man. Very thorough
Here thanks to Paul Danner. Interesting case. Great job! 👍
Really like how in-depth you are. Fitting for my learning needs subbed!
Haven't done much scope work on gdi injectors. Great explanation on your capture, and an overall great diag. Keep em coming! 👍
I notice that when the 65V shuts off; the #1 had 2 pulses of ringing. The #6 had only 1. I would not expect that to vary with injector on time. Don’t know if it’s significant. With the isolated input of the Pico, one channel’s leads can be connected across the injector so as to show the actual voltage response of the injector. Or a math channel could be set to show the composite waveform. I think it would be easier to spot differences that way. The same goes for looking at a CAN bus.
Muchas gracias por compartir esos hermosos diagnósticos y técnicas
Simple test accuracy makes a difference good job buddy
I'm curious if current (work being done) would have picked up anything useful vs voltage. As I see also had p300 misfire. Or maybe only would have shown up when it was bad enough to feel the misfire.👍
That's an interesting waveform, almost as thought the circuit is both power side and ground side switched. Is 65 volts a normal voltage for these? It seemed to go on for too long for it to be an inductive spike.
Great info thank you. The OHM meter lives on.
Very good video. I am curious if the current waveform would show something of interest. Thanks for sharing.👋
Nice diagnoses, and taking the time to share with us. I wanted to ask if you had build a math channel of channel A voltage divided by channel B current / you would have a resistance display channel which would have been nice to see a dynamic display of work being done. Just a thought and wanted to see your thoughts. thanks.
hi, thanks! wondering, if an amp clamp on pico would have shown some difference between the good and bad ...
😄 Injectors.!! I'm just glad I'm not the only one that gets the multiple vehicle repeated problems. Mine usually show up in two's back to back or 3 within the same week. Lol Only good I see about it is...your mind set is already in that game to diag.
Cheers Bro 😎👍🍻
🤔hmmmm another injector, always something to learn in every situation thanks 👍🏼👍🏼👍🏼👍🏼👍🏼
Another excellent video! Really would information! reminds me of a 2011 QX56 with P0300 the dealer had recommended new engine harness, ECM, Injectors and one relay. I did what you just did in this video! Thank you for sharing!
Your a diagnostic detective 😊👍nice work
Good diagnosis. Your channel is going to grow fast
I bet we missed all the fun of pulling that injector out. If you're lucky the others don't go bad after. I would replace the whole bank. Sometimes fixing these things costs a lot of money. Don't let it eat your time. GM injectors are not that good. Great job and nice equipment.
Love your cbannel, thanks for a great vidio.
I wonder if you measured both voltage and current, and then using the math channel you could have divided the current into the voltage which would have given you a dynamic resistance reading on the scope.
@@autodiagyt Start playing with it, Pico math channels have a lot of diagnostic uses from plotting crank shaft frequency to finding intermittent parasitic drains. CTI Research & Development channel has a really good class on it. Agreed, Darren is pretty good as well. The Pico channel has some good stuff on math channels, so does Super Mario.
THANK YOU I! FOR ALL YOUR VIDEOS ITS REALLY HELPFULL) I LEARNED A LOT FROM THIS DIAGNOSIS
Oh snap!
Man these GDI systems really don't seem very long term reliable... Plus are sooo much more expensive to repair for the customer! I usually reuse the fuel lines to avoid wasting resources and paying GM more money 💸😅
@@autodiagyt yeah I see that point of view for sure. Do you also replace all the combustion seals on every injector every time the rail is pulled? There is a chance of harming the good injectors every time those seals are removed and pressed on... Another reason I'm not a huge fan of GDI lol
@@autodiagyt Not too bad. Hyundai parts cost is WAYYY worse...like almost $1,000 to replace one injector by the book, or $3k for all 6
I am wondering if the injector on your last video causing trims imbalance would have any continuity to ground too, just like this one. Thanks
Pretty interesting case... Well done job man...
Hello from Sand Mtn good video, good find using an oldie but a goodie the old ohms test, I have found that when I have one of these with a bad injector that after a little investigation I usually find the rail was taken off prior to the fault, you know as well as I do very easy to damage these during removal
It's weird how it kept changing. It started at 1.55M and then went to 1.45M and on your last test it was down to 1.37M.. The one other thing that I would have looked at closely is inside the connector of the injector. If it somehow leaked some gunk down into the connector, it could simply have a little build up or corrosion bridge from one pin to the next on your injector connector-- where you may have been able to just clean it out and then maybe the injector would test fine after that. (it's possible :)
Otherwise, 1.55M ohms on a 12v can only pull 7.72 microamps, Which means there would be almost no voltage drop across it; so it's so incredibly small that I'm actually surprised that the computer could sense it.. Even your scope likely only has 10M ohms per volt of resistance, while measuring voltages.. And our scope/ DVOM's are essentially considered imperceivable to the circuit-- and this short was beginning to approach that same realm....
The fact that it was changing every time you tested it again, makes me think that it must have changed so drastically, possibly after heating up, that it spiked the driver enough to trip the code.. I think it was just the fact that it was only 1.5 ohms rather than 1.1 ohms like all the others, so it was actually not pulling enough current, and that's what the computer was sensing, and not that Mohm short.
It would have been really cool to see you cut open the injector with a cutting wheel. Particularly in a way that we could see behind the connector.
@@autodiagyt Right on.. my mind is still just curious as to what is actually happening. lol.. I wish you could cut it open; maybe something is obvious. I bet the problem is just right there at the pins, on the inside.
Thanks again Jake. Have a great week.
great video i like your progress.
Really great video boss..❤️❤️❤️❤️
PCM probably does a circuit test and gets pulled down and thats how it knows there is a circuit issue. Though, to protect itself it should not fire that injector because it would know there is a short which would damage internal transistor. Perhaps some engineer can help us explain what tests the PCM does during key on.
New subscriber excellent informative video. Thanks for sharing 👍
Jake I thought the pental signal looked different from 1 to 6. Might just be me.
I am only guessing but if I wanted to see something in the scope trace then I would overlay #1 & #6, not #1 & #1 or #6 & #6. The added resistance may show up in a longer trace going back towards 0 after the injector was done firing?? Thank for all the great videos, in the process of watching all of them and all future as a SUBr.
Checking injectors cold and hot is a requirement, they are all hot so all measurements hot should be in the same neighborhood, as you mentioned, you will not be looking for the cold spec while hot. Showing the after the fix measurements is also a LIKE to see from your viewers according to the feedback on many other auto repair videos.
How about checking the amperage too. The pcm may use that to fault check the injectors. KOEO amperage ?
I've done a lot of them I use the lines over never had a problem
Hello Jake,
Where is your shop located in the South?
Thank you Jake,
Have a blessed day.
I was going to ask why you didn't test both wires for a partial short to ground. At first I thought maybe the pcm shares a 12 volt internal for all 8 injectors (like it does for the 5 volt) and there was no need because all 8 would be effected . Then you tested it thought gone, Awesome job.
What a great diag.. Million likes ❤️❤️❤️❤️❤️❤️❤️❤️
Interesting, I wonder if the scope would have shown anything if you had driven it under load like the last one but then again you didn't have to since the ohm check showed an obvious fault in the circuit.
That an awesome diagnostic.I'm having trouble with my injectors too with my 2021 chevy silverado with a code of P02EF,P2B09 AND P2B95.Hope you can help me out.More power...
Which engine?
5.3L@@autodiagyt
@@edmondmanalastas5714 you should be able to follow this video for testing.
I have followed your test, good resistance in every injector. Ground is good. Those code are only on injector #2.
2015 silverado 5.3
P0205 misfire I replaced the #5 injector but still having the same issue and the same code,,, Tested the injectors for resistance at the main connection by the fuse box (1,3,5 all on the same fuel rail) have readings all others are reading 0L
please help! thx
I’m not sure what connector you are referring to. The ecm connector? Just make sure you are on the right pins and the terminals are not spread.
@@autodiagyt Yes ecm
I'm having same issue with my 2014. New pcm . Changed number 6 injector twice. Even ran a new wire from pcm to number 6 cylinder and still getting the PO206 code. But all 8 injector wires only say 6 to 8 volts... and my injectors ohm out to only 00.6. I'm lost
Interesting
1.4 megohms isnt much of a short for the computer to be complaining about. GM made a bunch of injectors for tpi engines in the 80s and 90s that would get shorts in the coil windings that might only show up when they were hot. The car would run for about 30 minutes on the highway and shut-off. The driver transistors would be overworked, from the kow resistance coils, and go into thermal cutoff, ending fueling abruptly. No codes, no start for about 45 minutes and it would fire right up. I thought it was ignition at first. Yay injectors.
Yup u got another sub'er here , Thx Paul Danner 💪👌
Thanks for your videos! I hate to see an ohmmeter win though.....
Show the fixes 😅 Nice work! Give us updates!
SUBSTANTIAL Automotive Diagnostics Programming
My teacher Automotive Diagnostics Programming
Wow can't believe that
Thanks for sharing what you know with us
Maybe wrong settings on your PicoScope
Thank you enjoy your holiday with all your family around you
SUBSTANTIAL Automotive Diagnostics Programming
From Nick Ayivor from London England UK 🇬🇧
New subscribers, good content 👌
New subscribers, thanks to Paul
Goes to prove the fact that multi tools are needed to verify the fault condition. Must retrieve my multimeter from the thrash can.
great work. keep em comin....
👍
The main thing I have learned is I don't work on GDI
You are very nice
Good job bro 👍
I was just going to comment about heating the injector up with a heat gun, beat me to it :/
👍👍👍
Great video brother keep showing us the tricks.thanks for showing us all