Whoas or Woes?
Thread Starter
Heel & Toe
Joined: Dec 2004
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Whoas or Woes?
I recently took my stock ex California 98 6spd silver coupe in to the local dealer for the steering column lock recall. The only change made was to reprogram the PCM. 20 minutes later I drove out. During a quick test drive on a lonely country road the engine seemed to have about 20-30 horses (seat of the pants feel) rustled out of the corral. No longer did my eyes go wide when accellerating. How can I get these ponies back? I have contacted GM customer service and they are "working on the case". After I had this done some of my fellow CLBG club members told me that horsepower loss is not uncommon. I wish I had checked with them or the Forum first! Thanks
Melting Slicks
Joined: Dec 2004
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From: New York NY
Cruise-In VI Veteran
St. Jude Donor '05
Have you previously had the car dyno tuned? If you have then the re-program of the computer would have erased the tune and you will need to get it reinstalled.
Thread Starter
Heel & Toe
Joined: Dec 2004
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Originally Posted by Icemanskis
Have you previously had the car dyno tuned? If you have then the re-program of the computer would have erased the tune and you will need to get it reinstalled.
Le Mans Master
Joined: Dec 2003
Posts: 5,561
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From: Atlanta metro Ga.
When this came up in a discussion on my local forum, the response from the local GM tech guru was that when the PCM is re-flashed, it resets the LTFT's to a "default" value. If that is true (it is a plausible assumption) then the power should come back over time.
The other possibility is that the timing map is different from what you originally had. I'm not certain of the model year details, but I do know there is a TSB about it, where GM decided they should roll back the timing a bit as compared to the earlier model years.
This is just another reason to not have the dealer perform the CL fix, since it basically does nothing positive (for you) on a 6 speed car.
The other possibility is that the timing map is different from what you originally had. I'm not certain of the model year details, but I do know there is a TSB about it, where GM decided they should roll back the timing a bit as compared to the earlier model years.
This is just another reason to not have the dealer perform the CL fix, since it basically does nothing positive (for you) on a 6 speed car.
Last edited by Dan_the_C5_Man; Dec 29, 2004 at 03:33 PM.
Team Owner
Joined: Sep 2001
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From: Lake Elsinore, CA
Strange you'd experience that dramatic a change with the 6-speed. When I first got my '02, I started experienceing a bit of detonation and discovered a TSB detailing a PCM reflash to fix the problem. This was early 2002. I took it in and had the PCM reflashed. At the time I had a Twin-Flow intake (which I had taken off the day I went to the dealer) and a Magnaflow/x-pipe catback. The tech told me the reflash basically pulled a bit of timing and that manual cars felt no real difference while A4's usually did. I felt no difference and most of the knock disappeared. I'm wondering if the LTFT suggestion above or the timing remap is what you're experiencing.
Thread Starter
Heel & Toe
Joined: Dec 2004
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I'm just wondering how I can get my original settings back. The idea of the pcm relearning the settings might be the best bet for now. Ofcourse the streets are going to have to dry up a lot here in So. Ky. before I can do that! Thanks all
