[Guest]

I have a 1990 Camry. The idle is very rough during warming up. Engine speed
would suddenly increase to very high for a few seconds and drop back to near
stall. It will repeat this before it's completely warned up (20-30 minutes
of driving in cold days). The engine will stall if this (surge and drop)
happens during acceleration. It only happens during warming up. It does not
happen if the engine is completely cold (first couple of minutes of cold
start) or completely warmed up (hot).

Does any one have any suggestions where I should start?

Thanks for any help!

Have a nice holiday!

 

[Guest]

what engine? I4 or V6? You can start by attempting to clean the
throttle body and in particular the IAC (idle air control). If the
V6, check that the intake hose from the air filter is not cracked in
the creases. Check the EGR valve and the ECTS (engine temp control
sensor) to make sure they are functioning ok.