some might remember I was plagued with cyl #2 randomly filling up with fuel and hydrolocking engine. Now for the umpfth time everything is back together, took Racelogics traction control completely out of the loop, brand new injector, ran a separate new wire from injector to PCM and guess what - AGAIN !

engine starts up nicely on 7 cylinders, but when you re-connect injector #2 and start stop a few times you can be assured that cylinder has filled up again. There is only the PCM left now.

Spoke with Ed and he can not remember that he has seen a blown PCM, apparently the driver must be bad or an internal shortage to ground, nothing else can trigger the injector.

How many had or have heard about similar cases?

 

damn havent ever heard of that happening...just another thing to worry about...good luck in finding/fixing the problem

 

had two

 

Like I said before, never seen an LS computer do it, but I have seen other types of computers have injector drivers go bad.
I would think that's about the only thing it could be in your case.

 

I've had to replace two LS1 PCMs in the past 5 years due to bad injector drivers. Very rare, but I've seen it.

 

When Reading the computer in HP tuners will everything work , Then when put in the car it wont run correct?

 

When you're reading or flashing a PCM, none of the drivers are even in use.

To the OP talk to CalEditor@PCMCalibrators about putting your Flash memory chip in to another PCM, that way you will not lose your tuning license on it.
I've seen drivers go bad, I don't remember any on the LS style PCM's, but very seldom was it without some issueoutside the PCM that caused it, such as a shorted injector, somebody running low impedance injectors on a PCM not made for them or a wiring issue.
You could also get somebody to change the injector driver in the PCM

 

I've heard of the injector drivers blowing when using low impedance injectors as they draw more current than the PCM was designed for.

 

Well I pulled the Tune with the Bench Tune Harness yesterday , and It all worked , and it all wrote. So not to sure Hmmmm ...

 

The drive could still be bad, since the pcm doesn't check them.
This reminds me of an issue I had a while back, one of the local garages that I sometimes do some trouble shooting for, called me about a vehicle they had, that randomly had a miss, but never set any codes. I had tries scanning it with my Snapon red brick and it would randomly loses comunacations,about the same time the miss wouldshow up. I figured bad PCM, so since it was a 411, I tried reading it, but it took several tries to successfly get the tune out, I almost told them I'd stop be the FM dealer and download the OS withmy bench cable, but after about the dofth try it did a complete read. A new PCM made the vehicle run flawlessly,so I decided to take the old one apart, as soon as I pulled the cover I saw the issue, it was all filled with moisture. I ended up pulling the board from it washing it good with contact cleaner, thern I dried it off and put it backtogether with another case seal. I gave it back to them and they put it back in and there were no more issues. So to make a long story short, did you by ant chance pull the cover off the bottom and make sure its not wet inside?

 

Seen one or two that have been bad and had injector driver problems but it's VERY rare.

 

You don't have to pull the flash chip... just read the image out and fully flash it into another controller. You have to do it with a tool that has no restrictions but in the end, he won't have to re-credit or re-license. It works; I did it today.

 

98 PCM - fuel pouring through #1 injector - no pulse control. PCM had a history of other intermittents as well. Checked injector, fuel pressure, wire to PCM, etc .Changed PCM, reflashed the tune and all was good.

 

Sorry to bring this back. Could that be possible with my car?

Here is my question regarding the PCM. I was using HP Tuners to build a base file for my car. I uploaded the file into the car and it ran great. Car idled real well and never died, it ran strong with no issues.

I than let the car sit for a while, since I had to do a few things to the turbo I haven't fired the car up at all. I took the turbo out, sent it out, got it back, put it back in and touched nothing else. The car sat for about a month.

The car now idles extremely rough, and dies out after about 15 seconds of idle. I've gone through everything to figure this out and now I'm thinking it's the actual PCM.

A long time ago the car did have low-z injectors with a driver box. It now has high-z injectors.

I just need to know that I'm not smoking crack.

BTW: The car is a 2000 Trans AM with a 2000 PCM.

Any help would be great.

 

This is going to sound crazy..... but while the car is running tap each of the injectors with a wrench, screwdriver, or small hammer.

I work on lots of seasonal toys and see stuck injectors from just sitting all the time

 

Along the lines I came to the problem with my PCM injector driver circuit malfunctioning and wound up replacing my PCM. Returned old PCM for core charge and installed the new one. Well I found some harness wires that were burnt and shorted and removed the harness and rewired it correctly. I ohmed the injectors and are in spec. Did a noid light test and found that my left inj. bank pulses correctly and that the right bank has no pulse. Voltage on left bank is 6volts. Right is 0v. Continuity is correct. Grounds correct. Harness correct. Codes shown is random misfires and injector driver circuit malfunction. Everything leads back to the new replaced PCM being the problem. I'm at a loss for words. Two pcms drivers going bad. I need some insight. What else is there?

 

The PCM doesn't provide power to the injector. There are fuses for INJ-1 and INJ-2 in the fuse box that supply power to each bank of injectors and the PCM just grounds the other side of the injector to complete the circuit.

The power side of the injectors should be 12v however and not 6v.

 

Hey guys I am having a similar problem already caused me to blow a rod and is still dowing it in my ls3 swap ... Found out Injector #5 spitting too much fuel causing engine to flood. I did a noid test injectionr getting constant circuit (is it a pcm problem? Or a grounded wire) hoping tomorrow I can run a separate wire from the pcm to the injector.
And go from there