Suggestions?

[LAKER-FAN]

About a week ago my wife's 03 corolla w/90k miles CEL came on. I had it scanned and it had some misfire codes and P0505. So I replace the spark plugs with NGK iridium's and the CEL light went away. The next day the light came back and it was P0505. So I removed and thoroughly cleaned the intake manifold and the IACV and the light CEL goes away when the car is warm, but returns when its cold. I also inspected the MAF and it looks fine. What else could it be? Any suggestions would be greatly appreciated

[mikered30]

When you said you cleaned your intake manifold, did you happen to mean throttle body?

How exactly did you clean your IACV?

I would replace (not clean) the PCV valve, and make sure you get it from the dealer and give them your VIN. It is around $6.

I would then clean the MAF with MAF cleaner.

If that does not work, remove the IACV from the throttle body: http://matrixowners.com/index.php/to...idepics-incld/

Follow that guide on how to replace the PCV and clean the MAF wires correctly. It is a bit of a pain to remove the IACV from the TB, so I would try things in that order first, since it appears you cleaned the IACV.

If that all checks out, it could just be a bad IACV if you are positive there are no vac leaks especially on the PCV lines and TB lines. You can inspect the lines and spray carb cleaner around them to check for leaks. Can you test the voltage of the IACV?


How is your cold and hot idle, does it fluctuate or is it normal?

BTW, Did your P0770 code ever come back on?

[LAKER-FAN]

I DID mean the throttle body. I cleaned the iacv very similar to that link. Wouldn't a bad pvc give me a different code? I'll clean the MAF. I dont have the propper tools to check the voltage on the iacv, but if the problem persist after replacing the PVC and cleaning the MAF I'll get a hold of a voltage meter.
My cold idle is a 1k rpm my hot idle is about the same.

[mikered30]

A bad PCV valve or PCV hose may not give a different code. The PCV valve is cheap and is probably over due for a change any way. After you clean your MAF and replace the PCV valve, disconnect your battery for an hour. Your hot idle is a bit high. Any loose or broken vac lines going to the throttle body?

Use this to check the voltage: http://madstyle1972.com/Repair/05/200o8c05/cip0505.pdf