Weird Problem....bad gas???
Thread Starter
Safety Car
Joined: Jun 2003
Posts: 4,509
Likes: 239
From: Coconut Creek FL
Weird Problem....bad gas???
I was on the highway this weekend in my 97 Coupe A4, driving about 70MPH and went to pass a few cars to get off at an exit...when I stepped on it- it downshifted then out of the blue I get a "SERVICE TRACTION SYSTEM" warning on the DIC, then followed by a reduced engine power indicator...I limped off the freeway and pulled into a parking lot- shut it down and let it sit for 5 minutes checking all my fluid levels, belts etc...when I fired it back up, I had full power restored and a CHECK ENGINE light illuminated. I limped it home (20 miles or so) and shut it down for about 30 minutes...when I fired it back up- no more check engine light and all has been fine???!!! it shifts normal, my temps are all fine and my fluids are ok?? I did notice that prior to me stepping on it to pass...it was girgling like bad gas knocks...I was about half a tank so I ran it alomost empty and put in a tank of Amoco clear 93 and have not had a problem since... 
Could bad or low octane fuel be the issue? I did let a friend drive the car a few days while I was on Vacation (never again!!!) he said he filled it with 93 octane...but from a cheap gas station...
thanks in advance!!
Could bad or low octane fuel be the issue? I did let a friend drive the car a few days while I was on Vacation (never again!!!) he said he filled it with 93 octane...but from a cheap gas station...
thanks in advance!!
Thread Starter
Safety Car
Joined: Jun 2003
Posts: 4,509
Likes: 239
From: Coconut Creek FL
Originally Posted by screw991le
What codes did you get?
Plus now there is no Check Engine or warning indicators on what so ever... will it store past codes?
TIA
Safety Car
Joined: Jan 2005
Posts: 3,896
Likes: 26
From: Manchester - Political correctness is tyranny with manners.
Originally Posted by byte_me
Not sure how to check them, I don't have a scanner...is there a way to do so like on a C4 by jumping certain wires on the ODBII connector and counting the SES lights?
Plus now there is no Check Engine or warning indicators on what so ever... will it store past codes?
TIA
Plus now there is no Check Engine or warning indicators on what so ever... will it store past codes?
TIA
The "diagnostic display" mode is entered with the following procedure:
1) Turn on the ignition but don't start the engine.
2) Press the "reset" button to turn off any warning messages
3) Press and hold "options"
4) While holding "options", press "fuel" four times within a 10-second period.
When first engaged the on-board diagnostics go into an "automatic" mode which shows all parameters: PCM-TCS-RTD-BCM-IPC-radio-HVAC-LDCM-RDCM-SCM-RFA. If there are no problems, you will see "no more codes" on the ICP display.
The computer will show two kinds of codes, "current" and "history," designated "C" or "H". A current code indicates a malfunction is present in the system whose module is displaying data. A history code indicates a past problem.
When the screen displays "manual diagnostics," select the desired module by pressing the "options" button to go forward or the "trip" button to go back. Press "gages" to go forward or "fuel" to go back.
To exit the diagnostic mode at any time, press "E/M". If you want to erase or "clear" codes, press "reset
Thread Starter
Safety Car
Joined: Jun 2003
Posts: 4,509
Likes: 239
From: Coconut Creek FL
Thanks!
All codes are marked with the "H" they scroll by so fast! nothing showed being current...there were 10 total "H" codes:
it said 10PCM 2 CODES whatever that means
Here are the ones I could copy:
P1221H
P1571H
C1278H
B0521H
U1160H
B2252H
B2286H
U1064H
U2253H
B2286H
It also said QC CODE 424421 in the very begining...?
All codes are marked with the "H" they scroll by so fast! nothing showed being current...there were 10 total "H" codes:
it said 10PCM 2 CODES whatever that means
Here are the ones I could copy:
P1221H
P1571H
C1278H
B0521H
U1160H
B2252H
B2286H
U1064H
U2253H
B2286H
It also said QC CODE 424421 in the very begining...?
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
97 and 98 C5 had a known problem with defective Throttle Actuation Control (TAC) modules. It will cause the car to go into LIMP HOME MODE and you will get the lights that you mentioned. My 98 had those symptons plus some others. I ended up installing a new TAC module, cleaning all of the grounds and PROBLEM SOLVED! A new TAC module can be had for about $200+ dollars. You can order one at Fred Bean or Fitchners chevy through there discound Mail Order. GM list it at $400+
My 98 got so bad that I was afraid to drive it in fear that I would get stranded!!
If you read and post your codes, it will help us see what is going on with the power train. Make sure that you include that the code is History "H" or current "C" It makes a big difference. Once you read and write down the codes. clear them, take it for a drive and see if any reappear. Start up and shut down the engine a few times and see if any come back.
Bill C
My 98 got so bad that I was afraid to drive it in fear that I would get stranded!!
If you read and post your codes, it will help us see what is going on with the power train. Make sure that you include that the code is History "H" or current "C" It makes a big difference. Once you read and write down the codes. clear them, take it for a drive and see if any reappear. Start up and shut down the engine a few times and see if any come back.
Bill C
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Man,,,,you were posting as I was writing!! 
If you hit the OPTIONS button while the codes are scrolling by it will go into MANUAL MODE and you can scroll through then at your leasure. Use the fuel and gauges buttons to pull up the mulituple listed codes and the mode button to go the the mext module.
If you press and hold RESET it will clear the codes that are in the module that you have on the DIC display.
Try that.
BC
If you hit the OPTIONS button while the codes are scrolling by it will go into MANUAL MODE and you can scroll through then at your leasure. Use the fuel and gauges buttons to pull up the mulituple listed codes and the mode button to go the the mext module.If you press and hold RESET it will clear the codes that are in the module that you have on the DIC display.
Try that.
BC
Thread Starter
Safety Car
Joined: Jun 2003
Posts: 4,509
Likes: 239
From: Coconut Creek FL
Originally Posted by Bill Curlee
Man,,,,you were posting as I was writing!! If you hit the OPTIONS button while the codes are scrolling by it will go into MANUAL MODE and you can scroll through then at your leasure. Use the fuel and gauges buttons to pull up the mulituple listed codes and the mode button to go the the mext module.
If you press and hold RESET it will clear the codes that are in the module that you have on the DIC display.
Try that.
BC
If you hit the OPTIONS button while the codes are scrolling by it will go into MANUAL MODE and you can scroll through then at your leasure. Use the fuel and gauges buttons to pull up the mulituple listed codes and the mode button to go the the mext module.If you press and hold RESET it will clear the codes that are in the module that you have on the DIC display.
Try that.
BC
I cleared the codes and will see if I get any more of them...I will check into the TAC you mentioned...is there any calibration that has to be done when installing this unit? Meaning can I do this myself or will I have to have it done professionally...
This is the first issue like this the car has shown...so it is probably this you mentioned...
Its going in for headers and catback tomorrow...so hopefully this won't exasterbate the issue...or non-issue as it were today!
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Safety Car
Joined: Jan 2005
Posts: 3,896
Likes: 26
From: Manchester - Political correctness is tyranny with manners.
Originally Posted by Bill Curlee
97 and 98 C5 had a known problem with defective Throttle Actuation Control (TAC) modules. It will cause the car to go into LIMP HOME MODE and you will get the lights that you mentioned. My 98 had those symptons plus some others. I ended up installing a new TAC module, cleaning all of the grounds and PROBLEM SOLVED! A new TAC module can be had for about $200+ dollars. You can order one at Fred Bean or Fitchners chevy through there discound Mail Order. GM list it at $400+
My 98 got so bad that I was afraid to drive it in fear that I would get stranded!!
If you read and post your codes, it will help us see what is going on with the power train. Make sure that you include that the code is History "H" or current "C" It makes a big difference. Once you read and write down the codes. clear them, take it for a drive and see if any reappear. Start up and shut down the engine a few times and see if any come back.
Bill C
My 98 got so bad that I was afraid to drive it in fear that I would get stranded!!
If you read and post your codes, it will help us see what is going on with the power train. Make sure that you include that the code is History "H" or current "C" It makes a big difference. Once you read and write down the codes. clear them, take it for a drive and see if any reappear. Start up and shut down the engine a few times and see if any come back.
Bill C
Per Bills advice, I replaced my TAC module bnecause we were having similar troubles in our '98. I have not had any trouble since doing that and it's been about 3 1/2 months and 6 K miles.
Good luck.
Thread Starter
Safety Car
Joined: Jun 2003
Posts: 4,509
Likes: 239
From: Coconut Creek FL
Originally Posted by DidntSettle98
Byteme...you have a Private Message.
Thread Starter
Safety Car
Joined: Jun 2003
Posts: 4,509
Likes: 239
From: Coconut Creek FL
Originally Posted by Bill Curlee
The TAC module is a plug and play install. No fancy programming needed!!
BC
BC
I got a price quote from Fred beans...$165 + $10 for shipping...I am getting it ordered tomorrow!
Cheers!
