zrater

the other day i made 3 runs and wide band was down at 12.5 af and it was about 80 degres out side with intake at about 90 on theses runs..

then i ran last night and temp was 49 degrees intake, cooled way down
and all 3 runs on the wide band was 9.3 af, the only diff was temp
90 one day 49 the other night. can u tell me y this is varying. thanks

racecar

Are you looking at a minimum or max reading, or is this your best guess of an average reading from looking at the histogram. I drive at about 13.8 and go to 12.6 at WOT with my latest tune. If I look at the AFR over 20 minutes, it runs from 10 to 18 at the high and low peaks.

Black02SS

iTrader: (36)

I think there is another problem that is effecting the AFR. If it went that rich, then the car would feel like a DOG. I'd almost bet that it wasn't a true 9.3AFR.

racecar

That's what I am thinking too. Either the reading is false, or there is something drastic wrong with the car. A 9.3 would be blowing black smoke out the pipes. A vacuum leak would make it lean, what would make it that rich??

SmokingWS6

iTrader: (1)

Try a free air calibration of the wideband. I once had somebodys read 7 to 1 for no apparent reason, We pulled the o2 out, did a free air cal and everything was back to normal.

I don't beleive anything in the tune should be causing it to run that rich, and you would of felt it missing very badly. If you were running in SD it would of been lean if anything in the 49* weather.

SSpdDmon

iTrader: (10)

Would you by any chance be in speed density? When I notice a 50* temp change in intake temps, I see 3-point swings in AFR while in SD. It's not as bad with the MAF hooked up, but more noticeable at idle and low airflow situations where the VE is being read in conjunction with the MAF.