Engine Performance problem
2001 Oldsmobile Aurora 6 cyl Two Wheel Drive 111, 00 miles
car seems to shift out of normal range, quicker when less torque applied. When reaching over-drive, the car shakes from a missing that occurs. If excelerate and down shift, the shaking stops but slight engine miss continues.
Engine used to miss (gallop at shift interval) when warming up. The discovery of cracked fitting for PCV valve and subsequent replacement stopped major gallop but now the shimmy-missing starts when engine is cold and remains when warmed-up. Prior to fitting repair, the check engine light came and stayed on. Since the repair, no light has appeared.
All fluid levels are good. Last tune-up was 16,000 ago.
Could oxygen sensor or MAF sensor be the problem?