OldSchoolSS

My car's been missing once in a while lately and is down on power. It really misses when under high load at low rpm such as going up a hill. The missing in pretty random sometimes it does it sometimes it doesn't. It the middle of the some chugging all 8 start firing again and it pulls pretty good.

I plugged in freescan and it only detects one 02 sensor right away. Once you start the car the other one will pop up in a short amount of time. I assume this isn't normal. Once they're both up they seem to work fine, although they stay in the lean range (.0xx .400) more than the rich range (.500 - .999) and my blm's are 123 and 125. I guess that explains why the car smells so gassy. I'm putting new plugs (NKG-TR55's) in and changing out the descreened maf that came with the car for a stock one off a 97 Z-28 that I have laying around. Is it time for new O2 sensors? I think they were just replaced before I about the car, about 15k miles ago. If so where's the place to pick up new AC Delco units?

Also the plugs I'm replacing are one year old and look perfect, really clean insulation, a little soot in the pocket and no visible wear on the electrode. The car also has 42lb/hr injectors that I changed the constants for to get in the ballpark, accel wires and an accel coil. The rest of the car is stock besides the EGR & AIR delete, a CAI, and a Flowmaster Muffler.

Thanks,

Scott

Injuneer

BLM's of 123 and 125 (in which Cells?) are really not that far off from normal, and wouldn't explain "smell so gassy". If the PCM is seeing O2 values below 400mV, it should be increasing the BLM's to bring the O2's back to swinging evenly on either side of 450mV.