Different AFR with A/C

EGHATCH · Post by **EGHATCH** » Tue Jul 05, 2005 4:56 pm

okay. car is running idle at 14.7-15 with no a/c. if i turn the a/c on, it will go to like 17s or 18s! so i added more at idle so its now idling at 14.7 with A/C. if i turn of a/c it will go down to 12s!

i know this is not normal, could there be a bad sensor?

DaX · Post by **DaX** » Wed Jul 06, 2005 5:27 am

Are you using shielded wire for your o2 signal? Could be interference...

EGHATCH · Post by **EGHATCH** » Wed Jul 06, 2005 5:36 am

im running open loop..

CivicVTi · Post by **CivicVTi** » Wed Jul 06, 2005 6:08 am

When you turn your AC on, due to increased load, the idle RPM rises (about 850 from 750 I think) and the car needs less vacuum to idle. SO you basically move right and down on the map from the initial idle (with no AC). Your maps might not be perfectly calibrated at this new area and that's why you are running lean.