I'm in a mess, any advice? [Archive] - GrandAmGT.com Forum


View Full Version : I'm in a mess, any advice?

09-06-2007, 09:55 AM
I hydrolocked my 2000 GAGT a few weeks ago in a flash flood. A new engine was just put in(Jasper). The only mods I have done are a CAI, DHP PCM, 180 therm., NGK plugs, Taylor wires, and a Camaro exhaust. The car ran GREAT before I hydrolocked it. The mechanic just can't seem to get the car running right again. The injector o-rings were torn and pushed out, the MAF sensor was shot, starter was dead. Those were replaced. According to the mechanic the car runs very sluggish and has a hard time going past 60mph. No codes have been thrown.
He checked the catalytic converterter and exhaust for the problem, no dice. Fuel pressure is good(filter and pump are new). Damn near everything has just been replaced and it still runs like crap. My mechanic is about to give up.

The only thing I can think of is the PCM or a sensor that has been overlooked. Could the PCM get screwed up from a hydrolock? I am probably as clueless as my mechanic as to what the problem is, can anyone lend some wisdom?

09-06-2007, 10:00 AM
Same year motor as the old one? Don't really know if that makes a difference

09-06-2007, 10:10 AM
Not sure. A remanufactured Jasper engine was put in. I'll look into that, though, thanks.

09-06-2007, 10:48 AM
Someone tell me, am I an idiot because it is obviously most likely the PCM, or is there a sensor (intake?) that can cause these problems?

09-06-2007, 10:51 AM
Is the air filter clean?

09-06-2007, 11:18 AM
Yes. It is an S&B Powerstack filter.

09-06-2007, 06:29 PM
The PCM is the last thing you want to blame. Its well sealed and surprisingly resistant to the elements.

Since this happened because of high water and the engine was hydrolocked, you couldn't drive it away and tell it was running differently.

One thing that possibly happened is the double-walled exhaust pipe in the DP to the cat might have cooled quckly enough to crush the inner wall and make a huge restriction.

This sounds along the lines of a cat or exhaust restriction to me.

09-06-2007, 07:05 PM
I don't think its an exhaust issue. Unless the mechanic is a moron he would've used a vacuum gauge to check for an exhaust restriction (I know I would) and if the restriction was bad enough to do that, it'd show up right away.

Though I do wonder if he has checked the vacuum with a gauge. These days "techs" rely more and more on computer codes, rather than "old school" diagnosis.

09-06-2007, 09:49 PM
Thanks guys. The only reason I would suspect the PCM is because I think maybe while I was fighting to keep the car out of the puddles the PCM had a reaction and changed the settings to accomedate for the lack of airflow, or something like that, and wont go back to the settings for normal driving conditions. A code was finally thrown today, so maybe I'll know more tomorrow. I also dropped off my stock PCM to help him troubleshoot, if necessary. He ran the car with the exhaust disconnected and same problem persists, crap acceleration and massive restriction at 40-50 mph.

09-07-2007, 08:52 AM
It turns out the PCM was the problem. The mechanic swapped the DHP with the stock one I dropped off yesterday and now the car runs fine. Thats pretty disappointing. I don't plan on driving that car for long without a tweaked PCM. What a waste of money that was.

09-07-2007, 09:07 AM
I just checked the PFYC website and it said there is a FREE one time re-flash of the PCM. Rock'n'roll.

09-07-2007, 09:33 AM
i just sent you a PM as I dont believe that the PCM was really at fault (dont know for sure) but if it was a reflash more than likely wont change anything

also is there anyway you could tell me what code was thrown?

09-07-2007, 10:42 PM
When I asked what code was thrown, he just said it was a TPS code.

09-07-2007, 10:46 PM
i agree on the pcm issue, there really should be any cause of a problem ...

tps issue? so he threw the reprogrammed pcm away and threw in a tps, sweet!

09-07-2007, 11:10 PM
i agree on the pcm issue, there really should be any cause of a problem ...

tps issue? so he threw the reprogrammed pcm away and threw in a tps, sweet!

lol. I know, I was assuming he didn't really check the code and just put in the stock PCM and said' to hell with this POS'. When I first talked to the mechanic about replacing the motor, he said the junkyard engine they were going to put in was called a LQ4. Last time I checked a LQ4 is a 5.something V8. Not to mention, when I got back home with my car today I looked over the body and noticed someone either hit the rear passenger bumber, or someone backed it in to another car. It was also great to see that someone tracked oil on to the floor mat and on the steering wheel.:applause:

The car still seems to run very well, no code, stock PCM. Now I'm not real sure what the hell to do with the DHP PCM. The mechanic also pointed out that a pin in the corner of the DHP looks pushed in, which sure enough, looks pushed in. WTH. Can anyone confirm that this is abnormal? The stock PCM doesn't have a stubby corner pin like the DHP, so I think this might have something to do with it.
Like I said earlier, the car ran great before this whole fiasco started.

09-11-2007, 01:04 PM
I just put the DHP PCM back in my car after taking it apart re-aligning the "pushed in" pin yesterday and the car works great I don't know how the pin got pushed in, but there is a scrape on the pin like something metal pushed it in. I'm not accusing the mechanic of sabotaging my PCM, but I honestly don't see how that could have happened from improper installation into the plastic socket/harness.
I sure as hell don't trust that mechanic anymore. This thread was a waste of time for me and anyone who has read it.

09-14-2007, 07:17 AM