JEDI87

I have searched but this problem is a little different. I occasionally get a cel, PO171, and it will stay on till I reset the computer. It will stay off for awhile, then all of a sudden it comes back on and stays on till I reset it. Is the light supposed to stay on or does it shut off when everything is running right? It's just kinda wierd that it goes off everytime I reset the comp. and stays off usually for about a week or 2. I've made a 180 mile drive the last 2 weekends and as I'm cruising it will come on, usually around 160 miles on the odo. You would thing that one of these times it would still be on after resetting it if it was bad.

UNR.Grad

I had the same problem as you. After giving the MAF one last good cleaning (brake cleaner followed by MAF cleaner) and switching to a trueflow filter, the light turned itself off and hasn't come back on.

JEDI87

I've cleaned it twice. After the first time it came on I cleaned it and it was fine for a few months.

iholla

what type of air filter are you using? Is it a paper type or oil like a KN

JEDI87

Paper.

johnw999

I had this problem 2 months ago. My TRD airfilter must have oiled up the MAF sensor after years of use. I cleaned the MAF sensor, but the check engine light kept illuminating (p0171 code). The idle was also too low. I finally just bought a new MAF sensor, and that completely fixed the problem. Sometimes the sensor just goes bad and can't be cleaned.

JEDI87

Yeah, I'm thinking it's bad but it's wierd that the light goes off for that long when all I do is reset the comp.It's also idling low and rough, not too bad though. It does that even when the light's off.

johnw999

Sounds very similar to mine. I reset the ecu, and the light would stay off for a while. It usually came back if I accelerated moderately at highway speed. The MAF sensor was $109, and I knew there was a chance that it wouldn't fix the problem. Fortunately, it did fix the 4runner. The stealership would have taken me to the cleaners if I asked them to diagnose the CEL.

JEDI87

Yep, sounds like mine. I guess I'll go pick up a maf and hope that's it.

Tikal769

Ive had this problem for the last 8 months. Ive cleaned the MAF, replaced my O2 Sensors, and Smoked tested for any air leaks. It all came down to a new MAF sensor.

Picked up a new one on Ebay. Locally they were $130, ebay got it for $30 plus $ shipping.

When It came in and I installed it, the light didnt go away. I was too lazy to reset the code =P Well anyway I thought all hope was lost on getting rid of that code. After 2 days of driving the code went away! Havent seen it for 2 weeks now. Replace the maf sensor.

Methos

I just wanted to say thanks to all of you who are posting on this site. I had the same P0171 code and was about 10 minutes from buying an O2 Sensor. I went and picked up a Mass Air Sensor and my problems went away. 2000, 4Runner, 2WD, V6. You guys have a great site!

Methos

HOJU

I'm getting quotes for $650! what the hell?

frodin1

Mine was doing the same and I soaked the MAF with cleaner and it hasn't come back on since. You can pickup a MAF sensor at Autozone or your local autoparts place if the dealer is to steep for you. $650 WHOA! What the .... That just aint right!

DoubleZero4x4

When I had to replace my O2 sensor, I had multiple codes P0171, P0133 and P0131. When I had to replace my MAF it was a P0171 by itself.

Is your gas mileage suffering with the CEL? I ask this because this was also a symptom when it was the O2 sensor.

If cleaning the MAF did not resolve the issue, replace it. My dealer price was $180 for my 2000 4Runner. $650 does not sound right at all.