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turbogtu
September 20th, 2009, 01:07 PM
First..I can't seem to get a good tune as a base. Anyone have any suggestions or tunes to shoot my wau...I put an LQ4 in my C4 vette. Has an LS-2 intake and injectors, long tubes, 92mm TB and a cam (605/609 Lift 238/240 112°LSA). I'm fouling plugs and running all kinds of crazy bad. Need it to be SD due to limited space for placing a MAF.

Next, I am continually killing pcms. I killed my first two before I realized my wall plug wasn't putting out enough amps. I just killed my third in the car.
The one I killed in the car was weird...went through the entire writing process without issue, then when it got to the reboot portion at the end, it failed. Is this one salvageable?

Anyone able to bring pcms back from the dead?

turbogtu
September 20th, 2009, 02:17 PM
One other question...as I'm looking at buying another pcm to kill. If I'm reflashing it anyways, can I use the pcm out of a v6 or 4cyl or are the pcms physically different on the inside? I realize that the pinouts are drastically different, but is it dependent on the programming and OS? Anyone ever try?

ScarabEpic22
September 20th, 2009, 04:38 PM
You need a PCM from a LS1 powered vehicle. Whether that be an Escalade, Silverado, or fbody it doesnt matter. Just the part numbers need to match, then full flash your tune into it and do a CASE relearn.

turbogtu
September 21st, 2009, 10:38 AM
Figured out why I killed it. I put my pcm secondary pulses per Kilometer Output Rate to 0....found another post where someone had the same problem. If EFI LIVE is listening, I suggest that if this kills pcm's then make the value adjustment between 1 and XXX. People will put that to 0.

Blacky
September 21st, 2009, 03:06 PM
We're listening - and investigating...

Regards
Paul

turbogtu
September 24th, 2009, 01:19 PM
Is it the 0 that caused it?

Blacky
September 24th, 2009, 02:28 PM
Still waiting on the test results...
Paul

turbogtu
September 27th, 2009, 01:02 PM
Although I found another thread claiming that setting the speed output to 0 can kill a pcm, and I did put that value to 0, I don't think that is not what did mine in. I got a new one, programmed it on the bench, when I put it in the car it was dead. I have some other issue going on with my harness?

Blacky
September 27th, 2009, 01:35 PM
We completed testing that issue here and found that setting that value to 0 (or any small value) will cause the PCM to die.

Our theory on why that happens is this...
It is likely that at some stage during PCM initialization that value is divided (as a whole number) by 256 or a similar large number causing it to become zero. It it then possibly used in a division and causes a divide by zero error which causes the PCM to reboot and start the initialization routine again, thus entering an infinite loop.

The software has been changed to not allow H0105 or H0106 to be set to less than 1000.

By all means double check the bench harness but please do not set those two values to less than 1000.

Regards
Paul

turbogtu
September 27th, 2009, 02:42 PM
you know that got me to thinking....I have set that value to 1240 on my tune that is killing pcms...do you think that 1240 is too low. I believe my stock vss used a 2k pulse per mile, that is what I was trying to accomplish.
At any rate....I'm up to 4 dead pcms now. I'm getting a chip programmer so that I can hopefully salvage one of them. What will I need to do to use the reprogrammed chip with the flashscan using one of my existing licenses? Also can I get the data I need to put on the chip...I don't know that I have any good ones to get the data from.

turbogtu
September 29th, 2009, 03:41 PM
1240....too low? I need to know before I kill another pcm. If 1240 isn't too low then I need to start looking at other components.
Also what on the other questions. I'm out of licenses so chip reflash is only option given my track record with killing these.

Blacky
September 29th, 2009, 04:01 PM
1000 is ok, we've tested the LS1 PCM at 1000 and it does not cause any problems.

Regards
Paul