Its been below 45 deg. in the mornings and my 96 started doing the exact same thing it did last year.
The throttle at cold start hangs a @ 1500 RPM and stays there. Will not come down
unless you let it warm up then kick the pedal (like a carb). Don't kick it and it stays there.
There has to be a TSB out there somewhere on this?

yea my L27 does the same thing on a cold start. It will start and then go to about 2000 and then drop down to 1500 and then stays there untill it is put in gear

thats kinda odd i wonder what causes it?

that is strange.. wat kinda oil are u using for winter? Durin freezing cold my car would idle @ bout 1200 RPM range.. then drop down as soon as it warmed up some.. I have switched to Esso XD-3 0w-30 in preps for winter.. last winter it would rev just a tad over 1K during cold start without heater block.

So you might want to try changing your oil.. and or try pluggin the heater block overnight and see if it does the same the next morning.

Possibly a bad temperature sensor?

Jay

Very good point.. so how would he go and troubleshoot to see if that maybe it? * I'm interested in knowing how that is done too for future reference *

I beleive it works off of resistance, so check the resistance and see if it is in spec for what the coolant temp is. Or, buy a new one for $7 and swap it in.

I was having a problem where my Trans Am would stall out when it was cold and I put it in gear. Changed the sensor and all is

Jay

I have the EXACT same issue in my 99. It behaves in the EXACT same manner...only does it in the winter and stays pegged at 1500 until the throttle is touched. It makes no difference whether or not the defroster is on (thinking it might be related to the a/c compressor).

This past weekend it was such a nusance that I scanned for codes and there are none stored. I'm not sure what to do next....so I just deal with it...and have for 3 years and 95,000 miles.

My '89 used to do the exact thing you are talking about. I don't know what fixed it.. but it just magically went away. If you don't have the MAF screen [removing this, started the problems for me], put it back on, and see if it helps. Otherwise, I have no clue.


-justin

My car is absolute stock (I'm not much of a moder). The MAF screen is still in the throttle body. The only thing that'* not stock is the upper intake, lower gaskets, and V-Power plugs.

I'd like to put an AutoTap on it to see if the PCM is calling for that higher RPM when cold.....and to last indefinitely!