IAC problem

[jerrykiefer]

90 Reatta idle problem..  Upon starting the idle goes to 1600-200rpm and remains there.  Hitting the gas after warm up has no effect. ( Maybe I'm thinking about an automatic choke).  Either way, if I turn the car off anda couple seconds later restart, the idle settles in at 650-700rpm.  Take the care for a spin and when you stop it will resume 1800=/- idle.  Computer shows no codes and drives as nice as can be.

Any thoughts, could the IAC be faulty?

Thanks in advance

Jerry Kiefer

[Ronnie]

IAC Cleaning Instructions

[jerrykiefer]

Gentlemen, thank you so much for the info, the morning project will be taking out the iac and cleaning it's orifice.

I'll report back any problems but look forward to a normal idle.

Jerry

[Dashmaster]

High Idle that won't change like you described might be  Throttle Position Sensor. when they go bad that will do this. Both of these can be checked via the CRT but since you have a 1990 you may see if any codes are present.  Bad  or sticky IAC usually will usually only come in to play when warmed up and in gear like sitting at a red light or stall.  Bad TPS will always give you high reading all the time, warmed up or not. 

Edited July 15, 2018 by Dashmaster (see edit history)

[Dashmaster]

The TPS is easy to check using an ohm meter. I think the procedure is on the ROJ.