Rough idle around 1000 - Update 1/16/08, Wasn't PCM.
Been here, done this with other cars. Check connections. All connections, especially grounds. How'* your battery? You need a good, strong battery with good connections to help "filter" the voltage you get from the alternator, which is by its nature rather dirty DC voltage. Soooo many times I have scoured over someone'* car with this kind of funky stuff only to find a bad ground, or several. My first one was several years back, same kind of erratic stuff, no one could find it... turned out two wires were frayed in a big harness, and when they got wet, they would share information and cause a hell of a problem. All kinds of codes, weird codes, unrelated codes, stalling, rough.. spliced in a few new non-green and corroded wires, problem solved.
Electrical, electrical, electrical.. I've seen it a dozen times!! So many sensors get replaced for no reason...
just my 2 cents worth..
Mike
Electrical, electrical, electrical.. I've seen it a dozen times!! So many sensors get replaced for no reason...
just my 2 cents worth..
Mike
Senior Member
Certified GM nut
Joined: Jan 2007
Posts: 1,646
Likes: 0
From: allentown, pa--brooklyn, ny

have you replaced your icm.?
on my 88 i had almost every symptom you named (got no codes like you tho
)
but after about a month of headaches it turned out the icm only worked when it wanted to.. car would stall while driveing as soon as i let off the gas.. but always started back up.. had bad smells from the engine not running right and kinda poor millage...
also have you checked or changed you fuel filter.?
on my 88 i had almost every symptom you named (got no codes like you tho
but after about a month of headaches it turned out the icm only worked when it wanted to.. car would stall while driveing as soon as i let off the gas.. but always started back up.. had bad smells from the engine not running right and kinda poor millage...
also have you checked or changed you fuel filter.?
Senior Member
True Car Nut
Joined: Dec 2005
Posts: 4,064
Likes: 0
From: August 07 COTM....NEBF '06, CEBF '06 OHMM '06 ONBF '07 CEBF '07

Werid smell, bad gas mileage, did you check your 02 sensor?
Also, is all connections clean and no wires touching (arcing) especially in the 02 sensor area.
and put in a can of dry gas and see if it helps any. (make sure it'* cat/O2 sensor safe)
^^^^^ suggestion came from this thread: http://www.bonnevilleclub.com/forum/...397&highlight=
Also, is all connections clean and no wires touching (arcing) especially in the 02 sensor area.
and put in a can of dry gas and see if it helps any. (make sure it'* cat/O2 sensor safe)
^^^^^ suggestion came from this thread: http://www.bonnevilleclub.com/forum/...397&highlight=
I'm new to this group and was searching out something else when I found this.
I have had some fun experiences with the TPS on my wife'* 93 SSE. My last TPS only lasted 2 years and I couldn't believe it could go bad again. Just sharing my experience in case this may be of help.
Symptoms:
Engine would erratically race at idle... anywhere from 1200 - 2000 plus.
Wife complained of dying in traffic (idle) & doing 45 without her foot on the brake.
Took a couple seconds extra to fire when starting.
Sometimes would need coaxed a few times.
Jiggling the TPS connector a LOT would make it change (slow momentarily)
Unplugging the TPS at idle (while engine is racing) would cause rpm to drop to normal.
I figured it was something in the connector/wiring
Work with the connector didn't help. So went after the TPS.
Mine (TPS) passed the voltage test.
HOWEVER, with it unplugged, engine off and throttle closed, it read rather high resistance (about 3k ohm). (center pin to end that should be lowest at rest)
I figured it should be closer to zero, so put a new TPS in.
That was it! The TPS. Wife said it was like having her old/new car back.
Don't want to waste your time or lead you astray, but the above checks are pretty easy to make. Bill 93 SSE
I have had some fun experiences with the TPS on my wife'* 93 SSE. My last TPS only lasted 2 years and I couldn't believe it could go bad again. Just sharing my experience in case this may be of help.
Symptoms:
Engine would erratically race at idle... anywhere from 1200 - 2000 plus.
Wife complained of dying in traffic (idle) & doing 45 without her foot on the brake.
Took a couple seconds extra to fire when starting.
Sometimes would need coaxed a few times.
Jiggling the TPS connector a LOT would make it change (slow momentarily)
Unplugging the TPS at idle (while engine is racing) would cause rpm to drop to normal.
I figured it was something in the connector/wiring
Work with the connector didn't help. So went after the TPS.
Mine (TPS) passed the voltage test.
HOWEVER, with it unplugged, engine off and throttle closed, it read rather high resistance (about 3k ohm). (center pin to end that should be lowest at rest)
I figured it should be closer to zero, so put a new TPS in.
That was it! The TPS. Wife said it was like having her old/new car back.
Don't want to waste your time or lead you astray, but the above checks are pretty easy to make. Bill 93 SSE
Thread
Thread Starter
Forum
Replies
Last Post



