jrock

During deceleration-open loop, AFRs jump to 17-20-if not higher. Should I increase the cell value on the fuel map for this area? I am just finishing closed loop tune...I am assuming I would move the cell value in the same
direction for WOT-open loop-with high AFR reads, correct?

thx in advance!

98/sc/390cc/walboro

ninjarunner

Nobody here knows...........

ornery

AFR's jump REALLY high during deceleration because your pumping the engine.. its not a problem and I dont it anything to do with you running open loop. My brother's turbo Civic does the same thing and its closed loop.

Edit: as long as it doesnt ping, I think youre OK.. I'd check other tuning sources though.

"Under very high vacuum (deceleration conditions) run 15.5:1 or 16.0:1 AFR's or even fuel cut on deceleration to prevent lean exhaust system backfiring."
- How to Tune and Modify Engine Management Systems by Jeff Hartmen

mt_goat

No, you don't want to add any fuel during deceleration. The A/F is suppost to go really high then.

Ian Rogers

you are in fuel cut, the ecu is cutting all the fuel to help with emissions