I have a strange question regarding the cold start fast idle. When I start the car, it idles like it would if it is warm. It doesn't matter how cold it is outside, or how long the car has sat either. My Buick that I drive every day has a fast idle, and when it's cold it will sit between 1,200 and 1,500 RPM until it's warm.
I don't know if this is a problem, but I find it odd that it won't fast idle. I seem to remember that it used to do this, but it would have been a couple of years ago.
Is there any I can look at to see if there is a problem?

 

Check the coolant temp sensor in the water pump housing. The PCM adjusts idle speed and cold-start A/F ratio based on the reading from that sensor. A4 cold idle is as high as 1,200rpm when temperatures are 3*F and below.

If the sensor is OK, check the IAC motor. That's what the PCM uses to set the idle speed.

 

I'll check those. I've heard that the coolant sensor can do this. I can use the procedure in the Chiltons manual, correct?

Thanks for letting me know.

 

You can check the coolant temp sensor using the procedure on Shoebox's website - much more reliable than Chiltons or Haynes.

http://shbox.com/1/4th_gen_tech2.html#ect