Engine Performance problem
1996 Pontiac Sunfire 4 cyl Two Wheel Drive 107000 miles
I would like to determine the root cause of a rough idle in my 1996 Sunfire. It idles fine when it is cold, but when the car warms up, it bucks like a mini bronco. (A big bronco would through me out to the car.) The bucking slows down and the speeds up. After a few seconds it seems to idle all right, and then goes back to idling rough. The car runs ok when driving, and the engine speed is above 1500 RPMs. I added fuel injection cleaner in the gas, and it helped, ever so slightly.
The ODB-II code displayed on the tester is P0171. The manual tells me that bank 1 (?) Is running lean. Is it the MAP Sensor? How do test the MAP sensor? Can something be loose?
Car has a 2.2L engine.
Friday, January 22nd, 2010 AT 9:03 AM