Problem with IACV, codes P0505 and P0100

THOMAS SHEA

MEMBER
2001 NISSAN MAXIMA
3.0L
V6
2WD
AUTOMATIC
145,000 MILES

Hi.
So on Sunday I was driving home and at a red light my car stalled, I got it to start once, but about a block later stalled again. After I got it home I did a code check and got P0505 and P0100 for IACV and MAF. So I order new ones for both, but during my reseach I saw two things that worry me. First many people say they had to replace the ECM at the same time because the IACV can burn it out. I took mine out and checked it and I did nit see anything that looked remotely burnt or damaged in the ECM. However, I do not know if it still needs to be replaced no matter what? Lastly the relearning of the idle, is this something I can do, or best left to Nissan?

Thank you.

1 Reply

KHLOW2008

MECHANIC
41,815 POSTS

When a trouble code appears, it does not necessarily mean the components related to it is faulty. It could be due to poor wire connections, accumulation of dirt, vacuum leakages etc. What you need to do is to check connections and in this case, clean the IACV to see if it solves the problem. You also need to check the air intake hose for leakages etc.

Whether it is necessary to replace the IACV or not, I would suggest cleaning the throttle body first.

Idle relearn for your model is self adaptable and does not need any special scan tools. What you need to do is to run the engine and let it self adjust. If the IACV comes with an idle control adjusting screw, you would need to adjust the idle speed with A/C running, when engine is at operating temperature.

You need not worry about the ECM for now. Do what is necessary first and see how it goes.