No fast idle when cold 1985
Thread Starter
Instructor
Joined: Jul 2004
Posts: 203
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From: Kelowna B.C.
No fast idle when cold 1985
Hey there! This morning when I went to start my '85 it chugged at around 300- 400rpm. I had to give it gas to keep it going then after about 2 mins.she smoothed out and everythings fine. On a restart she idles smooth, but there is no idle up to 900 then settling down. just 550 rpm right away. Advice please! Thanks!!
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Originally Posted by AGENT 86
Check the IAC and CTS connectors. Maybe one of them is loose.
The IAC (idle air control) is located under the TB (throttle body) and may need to be removed and cleaned along with the TB. The CTS (coolant temperature sensor) is located on the front on the intake manifold next to the CSV thermal switch (cold start valve). The CTS can be ohmed to check the resistance. Using a ohm meter after disconnecting the connector and stick the leads in the CTS. Post back the results and what the engine temperature is. Check connections on the IAC and CTS.The CSV is a 9th injector used on the 85-88 corvettes. It's purpose is to help cranking times when the engine temp is below 95*. After 95* the CSV is no longer functional...period. It is controled by the thermal switch mention earlier and as the engine temp gets closer the the 95* the switch will cut off signal to the CSV. This injector and switch is not controled by the ECM as is the other 8 injectors. It gets it's 12v from the starter solenoid. There also is a fuse behind the DIC in the dash...5a fuse.
The suggestions gived above me, will give you some things to check.
It was just a loose connection at the coolant temp. sensor!! Thanks for the responses!
j/k
