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Well Fuel pump replaced. Issue seems to be solved. no stalling thus far. The filter seemed to be pretty clear too. Interesting the Fuel Pressure didn’t increase. With the bad pump it was 53 and with the new pump and sender it is 52. Still out of specifications, but it is holding pressure now.My dad said the dealer charged him ~900$ to change the F/P, F/F ~6yrs ago. I’ll tell ya, those connections were sooo rusted I ended up twisting them off and had to get a new sender. I am skeptical the F/P was ever changed.
Anyway, thank God for the forums and videos! This has given the do-it your-selfers more tools and confidence. I think I learned more over the past couple of months on this than I did in 2 yrs of highschool autoshop back in the early 90’s.
glad to see the fuel pump is resolved. The pressure is still low. the next thing to look at is constant 12v
to the fuel pump. then the fuel pressure regulator. good job so farC8-)Lightning strike most likely means computer guy. Check fuses first then you can get a connector view schematic for the PCM and check all your power and grounds coming in and out of the PCM. I’m guessing your PCM is shot man.
It has been my experience that many electronic components fail once they get hot, or even warm. I would check the ECM relay. Actually, I would just replace it, they’re cheap.
When it stalls, does it restart right away?
If not, check to see what your missing. You know the drill C8-)
right spark or fuel.
Lightning-module/coil replace. Now starts, but stalls.Generally when it stalls I turn the key to the on position and listen for the F/P. When i don’t hear it it usually don’t start. When I hear it it usually starts. I guess I could disconnect the F/P and put a meter on it to see if it gets 12v after it dies. feel like this is working backwards.
Since OBDII wont connect to PCM, how can I check that without resorting to Chevy Dealer?
I notice when I turn the key to the on position, truck not running, the oxygen sensors get really hot, is this normal?
O2 sensors getting hot is normal as they have heaters for that very thing. The fact that your fuel pump doesn’t seem to energize all the time may be an important clue, find the reason for that and I’m pretty sure you’ll find the problem (perhaps an ignition switch problem). As far as I know the fuel pump should energize every time you turn the key to the ON position for at least a few seconds. I think a wiring diagram of the ignition circuit would be a great place to start looking for possible causes. BTW security systems are famous for doing stuff like this so if you have an aftermarket security system you might want to disconnect it to see if the problem goes away, it could also be an issue with the factory system but any add-ons would be suspect first.
My Dodge had a problem like this a few years ago, and the entire computer needed replacing. It wasn’t struck by lightning, just went haywire one day and would randomly cut the entire electrical system off as if the battery disappeared. It would always start the first time and would usually run for up to an hour before dying, but it could be any length of time before it would act like it had a battery again. Replacing the computer fixed all the problems.
Does this condition happen mainly after the vehicle has been running a while or does it also do this on a cold start up?
You could also do some voltage drop testing on the fuel pump circuit also.
Yea I think more testing is necessary. Since it seems to be turning the fuel pump on and off I would be checking the fuel pump circuit for problems, if you have a security system that would be suspect as well as they sometimes shut down the fuel pump circuit as a measure of preventing theft.
Alright lets go ahead and close this bad boy out.
Broke down and took to a dealer and paid $45 to get a diagnosis. They also said ECM.
Had NAPA order it yesterday. $116. +70 core charge. They flashed it for $40 I provided VIN and mileage 218,000. I installed it started and ran good several minutes. I shutdown, hooked up the OBDII and put key in the on position. Bingo, immediately connected. No codes the brake lights now work. Started and it ran a long time without stalling. So this time…. I think I got it (knock on wood!) Thanks everyone for the comments. Hopefully, someone will find this useful, I know I did.
It’s good to get Dirty/The zap must have hurt the ECM. I”m glad that you got it sorted out.
thanks for the fix and the update
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