Low idle speed when start cold engine

[camry98cool]

I had starting problem before, see:

Engine hard to start when cold or wet

First I replaced the dirty front ignition coil, it was same as before. Then I replaced the valve head gasket and coolant temp sensor, then the cold engine could be started without pressing gas, but the idle speed is very low (~400 rpm) almost can stop immediately, but it always struggles to start, after driving for a while, everything goes well. Now I am doubting the K&N air filter might be added over amount oil so it affected something or some fuel leaking or sensor problem?

Any suggestions will be appreciated!

[DFBonnett]

Could well be the IAC valve as mentioned in the other thread. This is a common problem. Have you cleaned it yet?

[Kep]

You might want to troubleshoot the Engine Coolant Temperature (ECT) sensor. The ECM uses that to determine the appropriate mixture for a cold or warm engine.

Kep

[camry98cool]

Originally Posted by DFBonnett

Could well be the IAC valve as mentioned in the other thread. This is a common problem. Have you cleaned it yet?

More than two persons said it wasn't matter with IAC valve, so I didn't do anything on it

[camry98cool]

Originally Posted by Kep

You might want to troubleshoot the Engine Coolant Temperature (ECT) sensor. The ECM uses that to determine the appropriate mixture for a cold or warm engine.

Kep

Yes, I replaced ECT as suggestions, nothing changes

[camry98cool]

After replacing Idle Air Control (IAC) valve, the problem was solved! A Toyota expert told me that this is a common problem for camrys