Hello,

My name is Jason from California and find the info you have here fantastic.

I have a 2000 Cadillac Deville Limousine, it is a livery package car stretched 130" by LCW. I like the looks, but cad's get trouble prone. I am hoping finding this forum will allow me to keep my Cad going. I have been reading forums trying to solve my problem, but just can't.

The car runs fine when cold, we drive it for a couple hours and when the car sits for 20-30 mins not running, it won't idle and stalls. No codes when running the self diagnostic feature it does not shows anything that would tie to this problem. I have cleaned the MAF, the idle control item. The motor and trans were replaced 35,000 miles ago at a GM dealer. The car has 97,000 miles total. this problem just started a few days ago and keeps repeating itself. It boggles my mind what would make it not idle after it cools a bit. I did notice before it happened today the car was idling around 1,000 RPM's in gear. I can feather it to idle around 375-450 RPM's. Any thoughts? Thank You

 

replace both crank sensors

 

It mainly does it after the car has been driven and sits 20 min. Do crank sensors just occassionally cause the car to run bad? Why can't it be the idle air control?

 

well anything could be the problem, the common problem on the 4.6L engine is the crank sensor failure.
but if u have a gm scanner , you can record what is happening in the vehicle then u can go after the fix
crank sensor will cause the car to Stall, No Start, Intermittent Engine Idle Instability
but if you have the money to spend take it to a dealership