MAF cleaning... Easiest project yet and a must.

[spanoulis]

I totally agree! This was a simple project I would not have thought about had it not been for my check engine light coming on. After taking it to Auto zone for testing, they could not find the fault code. On a whim I decided to try this. It worked! Light went out. Car definitely runs just a hair faster. Cost is minimal, (especially compared to taking it into the dealership for diagnosis), time investment is minimal. Just do it. Your car will thank you.

[aahighfly]

I have had two occasions with the CEL light on my 2001. Both times I had a rough idle at start up and the car would sometimes blow smoke on the initial start. The first occasion also followed the installation of a K&N air filter. I didn't notice if I had run the car previously without a thorough warm up or not, as mentioned by another post. My mechanic claimed it was a faulty air oil separator and coincidentally the MAF sensor also needed replacement both times. He blamed it on infrequent driving and long intervals (5000k miles) between oil changes. $1250 for replacement of both, each time. Research indicates a faulty air oil separator can cause high manifold vacuum causing oil ingestion into the induction system, which could explain the smoke and contaminated MAF sensor. I am curious why the air oil separator would fail, how it fails, and why my mechanic would not clean my dirty MAF sensor instead of replacing it. (other than greed of course). Any expert knowledge on this problem? It sound common considering the number of posts.

[mikefocke]

And your car is more than a few years old and the plastic is exposed to repeated heat cycles. It generally fails by cracking in one of several places.

The AOS tubing enters the airstream downstream of the MAF. The MAF is generally contaminated by a dirty air filter or over oiling of the K&N air filter...which isn't the best filter, incidentally, as it lets through more dirt.

Normally, if an AOS failure contaminates something it is the O2 sensors in the exhaust system. And the throttle body.

[shlim8]

Finally bought a can of air maf sensor cleaner and eagerly removed the maf to clean....

Unfortunately (or fortunately..._), my maf is absolutely clean, so clean that I didn't even bother to use the maf cleaner... This is a 2001 base box with 44k km... I guess the stock air filter works well !

I should be moving on to a pipercross or bmc filter soon, would be interesting to see if the maf get dirty then...