Im gonna try and sum things up so you dont have to read a three page novel. I get the car towed from SuperChevy because as I was going down the track (right after the 1/8 mile) the car just fell on its face. The RPM's shot down to 1500 or so and i just ended up coasting into the pits.

Shut the car off and as I was about to leave, go to turn the car back on, and it will not start and never did start.

Ge the Car towed to the dealership. Dealership says its your PCM (Ed Wrights PCM) that is causing this problem. I tell them prove it. They take a STOCK pcm put it in my car and my car fired up. It idled for just a few seconds (because my car can barely work with stock tuning) but nontheless it started up.

Talked to Ed about it and he has no idea what it could be. He said he put it in his car and it drove fine! So moral of the story, i got a car sitting at the dealership and when you put the stock pcm in it works. Put Ed's in it wont work! Guys, where do i go from here???

Thanks!!

 

Tell Ed to put that same program in another PCM and send that to you and then you'll send him yours.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Chris Jones:
<strong>Tell Ed to put that same program in another PCM and send that to you and then you'll send him yours.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Ed "told" me that he did that. However when i got the newer one back from him it still would not start. However, put the stock one in there, and it will fire up. how weird is that

 

How about having the dealer "flash" your PCM to make sure that the PCM itself is okay and will run the car. Then pull that one and have Ed do his thing again... OR, just buy LS1Edit and do it yourself!

 

With just a 224 cam and bolt ons your car should run with the stock PCM - you may have idle issues, but it should run.

It sounds to me like you have some other problem, and the Ed Wright PCM is simply exacerbating the problem.

From your post it sounds like your car was running fine for the time, and something happened part of the way down the track. Now it won't run anymore with the Ed Wright PCM. Unless a hard part in the PCM somehow failed (very unlikely) that doesn't sound like a computer problem.

How are all your other sensors reading with a stock computer (or can it run for any period of time?)

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by ChrisB:
<strong>
How are all your other sensors reading with a stock computer (or can it run for any period of time?)</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Chris,
When they put the Stock PCM back in, it fired up but only for about 1-2 Seconds. With the Stock PCM the car would start but it would not start for very long at all. I thought that was kind of weird too because I thought that I could atleast be getting my car to start with the Stock PCM for a decent amount of time.

So the Stock one Turns the Car on for a few seconds, but Ed's only can 'crank' the engine but not turn it on. What the hek is going on here?

Chris,
After they started the car with the Stock PCM, (they started it bout 4-5 times and each of those times the car would start for only a split second) I checked the Shrader valve and saw barely any gas around the cap. Usually i see more gas.

 

I thought there was a certain restart process you have to do when you physically change the PCM to get the car to recognize it. Either way if the stock one works and the "Ed" one doesn't, he needs to fix it.

 

ChrisJones,
I never heard of that. All the other times i've popped in Eds PCM into my car, i have just disc. the harnesses and popped in the new ones and put the harnesses back on.

Chris from SpeedDemon,
you got me really thinking now as to why my car would barely start with the stock PCM,(notice i say barely) but not at all with Ed's.

 

I swap pcms regularly with no hoopla. I wonder if you split the hose on the fuel pump. When mine split i had 20psi of fuel pressure. If ED leaned your car out for the cam, it would make it next to impossible to start with low fuel pressure. Stock programmed pcm may be rich enuff to get it to start. I could druve mine home with 20psi but it took a few secs to start.

 

ether that could it be the car alarm cutting fuel? Did ya try another key?

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Chris Jones:
<strong>I thought there was a certain restart process you have to do when you physically change the PCM to get the car to recognize it. Either way if the stock one works and the "Ed" one doesn't, he needs to fix it.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">This is true for the Corvette, not sure about F-body. It's a VATS/BCM thing.

 

This may sound really stupid, but check your ignition relay. Last week, my car would start fine sometimes, and others takes 10-20 cranks. Then it would just all of a sudden not start. One out of 100 times, it wouls just amazingly start. Turned out to be the ignition relay. It somehow was screwed up enough to not work most the times, but could still flip for that freak event and start the car. This had me stumped for a good day, and I tried everything including replacing the crank sensor.

 

There is a fuel pump relay in the PCM. Before firing, just put the key in the 'on' position. You should hear the fuel pump turn on for a few seconds.
I found this out when I got an ED Wright program on one of his used core trade-ins. It had a bad fuel pump relay inside the PCM.
ED send me a new Programmed GM core overnight & it's a-ok.

Dave

 

How about this for a theory!

1) you put in Big injectors, and Ed compensated for them.

2) Your Fuel pump or system went so you now have Low fuel presure.

3) The stock PCM delivers more fuel, because it thinks you have smaller injectors, so it will run, while the tuned one won't.

Ken

 

Cablebandit: I just got an ls6 intake installed the week before. is it possible to split that hose with the install of an ls6 intake? If its not, then i dont think i have a split hose.

CoolZ28: i haven't tried another key. I haven't really thought of that. Maybe on Monday i can go down to the dealership with my spare set and try and see if it starts.

The thing that gets me is that after we started the car (for just a few seconds) with the stock pcm, i popped the Schrader (sp?) Valve and saw barely any gas at the tip, little if all. Now i do realize that the car would only run in 2-3 second spurts. However, wouldn't that be enough time for me to see some gas off that valve when i unscrewed the cap?

 

Yep, if your fuel pump is working you should have fuel pressure after key on. Put a fuel pressure guage on there and watch it on key on - it should spike up, then drop back down to about halfway. When cranking/running it should be at full pressure.

 

ChrisB:
I did a fuel pressure test when i had Ed's pcm in and it came in at 0. I did not do a fuel pressure test when i had the stock one in. That might be a good idea to do.

xssive: where exactly is my ignition relay?

2000Firehawk: i think i will go down to the dealership tomorrow and see if i can hear the Fuel pump whine for a split second with the Stock PCM in.

Do u guys think that with the stock PCM my car should be able to turn on for more than a few seconds? Theres got to be people running on a stock pcm with only a Super Thruster and a Thunder 224Cam. Theres got to be something im missing. To the dealership tomorrow :sigh:

alright, thanks guys for all your help. I'll check back tommorrow, gotta get some work done.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by SSBoy:
<strong>ChrisB:
I did a fuel pressure test when i had Ed's pcm in and it came in at 0. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">There is your problem, stop worrying about the tuning/program.

If there is a fuel pump relay in the pcm that could be your problem (though I was not aware of one).

Otherwise you need to diagnose the no fuel pressure condition - e.g. 12v to the pump - do I get pressure, clogged filter, bad relay, etc.