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2003 Seville sporadically dying after start due to low idle. No code shown.

1642 Views 7 Replies 3 Participants Last post by  Submariner409
Thank you in advance for any advice on this issue, I'm not very knowledgeable about cars in general but have learned a lot in the past year with the help of a few car savvy friends.

The title pretty well sums up my issue. My 2003 Seville is dying after start up, I've had one code pop up after the 3rd or 4th time of dying (p0507) but after checking it, it was cleared by the auto parts store I went to. It has not given a code since that day despite still having issues.

The car has never died at speeds of 30mph or higher and I've gone weeks without an issue then it'll happen again. Sometimes the idle is higher than it should be and sometimes it dies. I've had it die twice on the way to a repair shop in the morning and in two days of having it they couldn't get it to die once. (Luckily they didn't charge me a dime.)

For quick reference p0507 states

Code Definition: Idle Speed High

Possible Causes:

-Engine Vacuum leak
-Idle Air Control has failed
-MAF sensor is dirty, "skewed"
-PCM has failed
-Throttle plate, throttle shaft or linkage is damaged or sticking
-TP Sensor is out-of-ranged or Skewed high

Thank you for any advice!
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Re: 2003 Cadillac Seville sporadically dying after start due to low idle. No code sho

I'm headed out to my father in laws for Easter here in a few, I'm sure he'll be able to help me clean the TB after festivities.
(I picked up some TB cleaner not too long ago so I have it on hand.) I'll give that a shot and see what happens. Thank you for the quick response!
Thank you for the suggestion. I stumbled across a post that sounded almost identical to my situation from a few years back and he said he'd tried a few of the options that are listed here as well as suggested by some of my friends/family but the post stated that replacing either the IAC valve or IAC sensor fixed the issue. I'm having trouble locating the post now because I found it at my in-laws and not on my computer. :(
The car has tripped another code, p1860. Yesterday it throttled high when driving to a job site and also died on me as I backed out of the auto shop that I checked the code at.


Code Definition: TCC PWM Solenoid Circuit Malfunction

I don't know enough about cars to know if this is a secondary issue or if they are linked. Could it just be a fluke occurrence or something caused due to needing to change out the IAC sensor?
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