[majdmd]

Originally Posted by Siriusarcher

Howdy
My first post here...
Thought I'd share what I've learned recently about the fuel delivery system in this car: Had the check engine light, with poor idling, poor acceleration (bogging when I hit accelerator), and occasional stalling at idle, which is a huge safety issue given the vacuum assist brakes and power steering.

Brought to my mechanic who found the p0172 (rich on fuel mixture). He diagnosed a failed O2 sensor, which was replaced, to no effect. After that, he recommended a new throttle body assembly thinking that the idle motor or throttle position sensor was pooched. These can't be fixed--gotta replace the whole TBA. I went to dealership, bought and installed the part, reset EFI, all to no effect. Finally, on a whim, I pulled the mass air flow sensor out (small philips screwdriver needed), cleaned it with a thimbleful of rubbing alcohol, a q-tip and shot of compressed air. Re-installed and reset compter (pulled EFI fuse B). Voila! problem solved! No bogging, better mileage, no stalling. Could have saved about $700 if I had tried that earlier. Consequently, I've got a perfectly good throttle body assembly sitting on my work bench. Anyone with similar experience?

I think car makers enjoy more sensors in the name of cleaner air. Everytime a sensor is dirty they run up a big service bill on the consumer. I just did the Q-tip method and found a thin black layer completely covering the MAF sensors (two tiny parallel sensors). Worse yet I found few filaments hanging on the two tiny sensors ( must have detached from the genuine Toyota air filter that is made of those filaments). I think Toyota should put it in the manual that first thing is to clean the MAF as it will definitley get dirty from the years of exposure to other cars exhaust.