My '92 Lumina 3.1 with 163K miles has an intermittant "Service Engine Soon" light that comes on and off every few minutes while driving. The codes come up MAP sensor and knock sensor...what gives?
Before I start replacing expensive sensors, I'd like tp know why my Lumina idiot light comes on and after a few minutes turns off while driving. It feels like for the few minutes it is on the engine does run rougher but then goes back to normal when the light goes off.
Also, the engine drips oil and leaves stains everywhere I park it...is there any effective aftermarket stuff I can add to the motot oil to at least slow down the drips? I thiink it's the rear main seal that's worn.