finnally got my car out on the road yesterday after i sorted out most of the problems. Computer seems to be having a hard time managing the engine. Id never know by the way its running. Idles real nice, good throttle response, has power, good all around drivability. The thing is the blms and o2s are all over the place. They range the full spectrum of readings. Again i wouldve never known just by how its running. Can i just chock this one up to needing a 350 prom to go with my 350 injectors or is there something more sinister at work like an inconsistent fp or something. It seems to be fluctuating alot considering the engine i put in only has about 30 hp over my lo3.

Rather than flap my jaw about what it does heres some graphs.

 

Your O2 volts should do that, with the stock switching type sensor. It should swing back and forth around 0.45 volts.

BLM's all over the place... heh. You should see my MAF car.

 

yeah... Guess im expecting too much out of a 14 yearold 8 bit computer. Is .5 or so thecorrect value for the o2? My plugs look like their a little too clean. kinda have a pinkish color to them. Maybe i just need cooler plugs.

 

wouldnt this also indicate the possibility of spiky emmisions. Ive seen some people post thier emmisions slips when they falied and they had lots of peaks and vallys in the co and hc output.

 

There's a graph somewhere on the PROM board that should the output of the o2 sensor vs. air/fuel ratio.

14.7:1 -> 0.45V

 

huh... very interesting reads. Guess ill want to learn alot more about how the gm ecm works and how to tune it before i decide to do any major mods to the motor.