ST162 idling issues.

[Howieau]

Hey,

Im having idling issues with an ST162 celica with a 3SGE. It idles fine (around 900rpm) when I first turn it on of a morning, or whenever it hasnt been driven for a while. But say after driving it for about 20mins + the idle drops to roughly 400 and seems to stay there. As a result oil pressure has been dropping aswell which I'm worried about. I've turned the idle up so that where it would usually fall to 400rpm it is now on 900rpm, but where it used to sit on 900rpm first thing of a morning it now sits on roughly 1,500rpm. Sometimes it jumps to 2000rpm in traffic. Its beginning to fluctuate more and more it seems, any ideas?

Many thanks.

[Dale]

Clean your ISCV

[ra23celica]

Pull the main engine fuse for 30 sec to 'reset' your ECU - it may have learned some bad behaviour.

[AndyTTR]

iirc the idle speed is controlled by an old-school wax float type of idle speed control, not controlled by the ecu.

My Celica used to idle weird (especially when cold) as air would get stuck in this idle speed control valve if i hadn't bled the cooling system properly.