Doc99SS

iTrader: (2)

From my other thread on an LS2 conversion, with the help of mainly two members here, we have determined that most likely my PCM is toast. The symtoms are no spark, fuel pump will not come on, fuel injectors do not pulse, and I tried to READ PCM this morning using LS1Edit and the "connection failed". Therefore, I need to understand what my options are. For example,

1) buy a PCM from GM and install it myself,
2) buy a PCM already tuned by a sponsor here, (who does this?)
3) can my PCM be fixed.

And of course there are many complication in my case. I have installed an LS2 402 stroker short block and top it off with my what I had on top of my wrecked LS1 block. See sig below.

I have LS1Edit, an early version having one license left on it. With LS1Edit, I am locked to my specific vin number. I am very comfortable with LS1Edit, but I guess that I could use a different tuner. After installing the new engine, I made a new LS1Edit program file to address to cylinder size, 39#/hr fuel injectors, etc. And, I have a very early version of ATAP.

moehorsepower

iTrader: (3)

If you cannot read or write to it, then yes you fried it, You must of lost connection while programing, Sometimes while reading and loosing connection the PCM will be in a Frozen state where the car will not start, all I did was remove the PCM fuse, Key on for a few seconds then Key off, this would fix the problem, I have had this happen maybe 4 times and it worked everytime. Other option is to go purchase another PCM, does not have to be new,make sure it is of the same year 99 up and not a 98 and if you have your program saved in LS1 Edit then flash it, or at least flash it for the injectors and get it re-tuned if you do not know how....

Doc99SS

iTrader: (2)

Yea, what happened to me was that when I attempted to upload a new program, the upload get interrupted due to low car battery power. I have done a PCM reset, and have (apparently) successfully uploaded the new LS1Edit file, twice.

Last nite a bought a new car battery, its in and powering the car now. I will do another PCM reset and key on & key off after the reset. I will then do another upload.

I have not completely given up on my PCM. Thank you for your reply.

Frost

iTrader: (45)

if it died during writing it's almost certainly no good now

wait4me

iTrader: (10)

If you send me the pcm i will fix it for you. Should only be 30 bucks.

Also if you just want a spare replacement pcm, i have 1000s in stock so i can get you one out asap. Usually around the 75 dollar range.

Doc99SS

iTrader: (2)

I have done anther PCM reset. Also, I have been able to conduct a READ PCM. I am continuing to look for loose grounds.

slow

iTrader: (7)

It sounds like you may not have a valid calibration in the pcm, it may need a write calibration to put that back, but you should make sure the grounds are solidly connected.

Ryan

Doc99SS

iTrader: (2)

I have uploaded a new program three times now and have been able to read it back. I have checked the read file and it seems good. I have checked PCM pins C1 1 & 40 and C2 1 & 40,,, all show continuity to the negative battery terminal.

The same problem continues, No fuel pump, no spark, no fuel injector pulse.

LS2TA

go on ebay get a new one its more than likely ur pcm or just find a used one

Doc99SS

iTrader: (2)

Well, my wife has a 2000 Camaro Z28,,, I figure to swap in that PCM. But she has not offered it up yet!!!!!

slow: I dont know what you mean by a valid calibration. I have upload the same program to my PCM three times now, using the same method as I always have. But,,,
(maybe you did not read this) prior to the three uploads, I tried to upload this new program, the upload got interupted due to low car battery power. I went out and bought a new battery and have successfully uploaded the program three times. The PCM still will not command the fuel pump relay, fire the plugs or pulse the injectors.

My grounds at the back of the drivers side cyl head are solid, there are two metal tabs under the bolt head.

What to do?

Doc99SS

iTrader: (2)

ALLRIGHT !!! The two ground wire tab which is grounded to the back side of the drvs head is broke,,, what I mean is that one wire of the ground wires broke away from the metal tab.

Viper

iTrader: (6)

That would explain not starting.

Doc99SS

iTrader: (2)

I fixed the ground wire issue and the engine started up right away. This engine ROCKS!
This is the biggest cam that I have ever had,,, I will probably be back here asking questions about tuning this cam.

Thank you to everyone for your replies and trying to help me, I appreciate it. This is a great board.

addicted2fun

I seriously love it when people fix their cars *cries* i wish i had a good story to tell like that.. LOL