Check Engine light is coming on, and I get a P 171 (engine lean) code from a generic OBDII scan tool. The motor revs freely at idle, yet the under load the car is very sluggish, and there is a burning smell from something overheating. I believe the smell is the catalytic converter overheating. The ECU has been modified with TME/IPD program, along with a TME sport exhaust, but the problem persisits with a stock ECU. I have been told that a MAS (Mass Airflow Sensor) may fix the problem, any suggestions?!
The Volvo is a 1997(1996) T5 wagon, with about 98,000 miles.
Regards,
Pete

the maf tells the computer how much air is going into the engine and tells the ECU, which then adjusts the fuel/air mix. could be the cat going bad, does it smell like rotten eggs?

dan
97 850 glt turbo

I've heard that the MAS can malfuntion, send the wrong info to the computer, lean out, run to hot and burn up stuff heance melting a cat up. I dont think that a bad cat would trip a lean code. Any Ideas?
Thanks,
Pete

I have cleaned my MAF sensor about once a year with Alcohol and Qtips. it is easy to remove from it's housing with the two torx screws that hold it in. just remove them and pull the sensor straight up out of the sensor housing. do not use carb cleaner or anything except alcohol. it is made of platinum and some cleaners can damage it.

it is suppossed to be self cleaning, when it heats up it should clean itself, but when i took mine out the last time it had noticeable gunk on it, if it gets a slight mist of oil on it then dirt will stick to it.

i clean mine becausr i have a Amsoil hi flow air filter (like a K&N) it is reusable and uses oil like the K&N. when it is reoiled i have noticed the MAF gets dirty after a about a week, i clean it then.

It will not do any harm to use the alcohol, a friend who owns a shop told me they clean MAF sensors all of the time this way.

after i clean it the car seems to idle smoother and runs better. worth a try.

Dan