2000 toyota 4 Runner ..code P0171

[santhecat]

I have had this code - P0171 come and go ocassionally for last 3-4 months.
It would go automatically and sometimes If I used to do 60mph it would come up again .

Now that my car is due for yearly inspection..I needed to get it cleared hence I took to a BJs Monro. BJs Monro checked it through the OBD meter which said "System Bank lean" for P0171 . They cleaned the MAF sensor and said that it required Fuel injector service which was then performed.

The car was handed over to me and driving less than a mile Check engine light came again. I took it back to monro which showed the same code P0171 " System bank Lean". The code was reset and I was told that since Fuel injector service was done it is taking effect. The code came again after 31 miles and was reset again. It again came after 30 miles ( P0171)

I had called them again and was told that it takes a while and sometimes 250 miles till I had driven to have the system record it and have it cleared again( i have already driven 125 miles since the MAF sensor was cleaned)

Am I on the right path or being taken for a ride ?
If not on right path what needs to be done ? Do I go to Toyota dealer ?

[Brian R.]

Try cleaning the MAF sensor with it out of the car. One side of the sensor is very difficult to clean when it is in the air cleaner box. It is the most common problem with P0171. Here is my experience:

http://www.automotiveforums.com/vbul...d.php?t=732698

I replaced mine, but cleaning the hard-to-get-to side might have solved the problem. Even after I cleaned it while it was still attached to the air cleaner box, it was dirty on the back side. I never tried the old one after cleaning the back side.

[santhecat]

It seems that replacing the MAF sensors as per Brian did the trick
I have been driving now for nearly 100 miles on/off ..no Check light
Had taken to Toyota dealer who charged nearly $275 for it ( $125 for part and $125 for labor) ...Just coming back from inspection and it passed