Hello, I won a 2001 Cadillac SLS and a few days ago my car on start would not idle properly. This morning on start up it would not stay at idle, it would surge down to 500 rpm, then 750 rpm, back to 500 rpm, then go lower, and just quite running. I decided to replace the spark plugs, and they needed to be replaced, yet the problem still continues intermittently. What could be the cause of this?

 

How did you win it? poker?

rough idle, pull codes & check TPS.

 

I own not won....typo....I wish I can win a car...Thanks for the tips...I'll let you know how it turns out.

 

This morning same problem but then Idle stabilized enough so I could drive. When I pulled into gas station it just quit running on it's own, dash went black. It restarted no problem, then after I fueled, it idled fine, and I drove off to work.

 

Yesterday I cleaned out Air Filter and Air Intake area, it was full of dirt. Then I also removed the TPS, cleaned and re-installed the same part. Car started right up and Idle initially went to 1200 rpm's then after a few minutes came down to 750 rpm's. Never had any more problems remainder of day, and Yes I started several different times. Outside air temp was around 60-70F.

Then this morning after a cold soak of around 32F my car would not idle anymore again, held gas pedal down for a while then it kicked in and started to idle. I drove to work, when I tried to park car killed itself off.

Decided to R/R TPS, and no help, same problem? Is their a cold fuel injector system for start-up? Should I just take it in and get a diagnostic test. Their is no check engine light ?

 

some cars, when you replace the TPS, the computer has to be re-trained, not sure on your model .. SLOWROLL ? you out there?

also, did you clean the coal deposits inside the throttle intake?
if you havent, be ultra careful with the butterfly and SEAFOAM spray can is one good choice of cleaner.


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I have yet to clean any coal deposits inside the intake but this morning my low to no idle went to super high idle? The outside temp this a.m. is around 50F and the car ran just fine yesterday. While driving to work I noticed the IDLE seemed high, when I went to park it, the IDLE was running at 1800 RPM??????? Shut eng off re-started no help? How do you go from a low/no IDLE to a SUPER high IDLE? Perplexed?

 

I have never heard of cleaning a TPS, so I am not sure what you cleaned. Coking of IAC and/or throttle plate can lead to unstable idle / stalling. TPS could be skewed (faulty, but won't set code). Since throttle has a mind of it's own a diagnostic test by a qualified tech is needed before something bad happens. If throttle body is coked up; cleaning maybe at added cost and required as part of diagnosis. Reading 1st posts what else happened when dash when blank, are there codes in any modules? Dash going blank without codes is not normal.

 

Found Idle Control Valve full of black soot, cleaned, lubricated..Idle went back to normal and has yet to mess up. Idle is now around 700 RPM, after a cold soak tonight, I will know if all is well in a.m. Thanks for all the tips...

 

The Outside are Temp was 35F this a.m. and my car started normal and idle was normal through out my drive to work. It appears so far the car is fixed, my IDLE problem is gone. I cannot believe the price of an Idle Speed Actuator...$400 dollars? It has 2 screws and a connector...unreal! Thanks once again...