Lean Condition in Between Shifts and After Blipping Throttle

FlashPro questions & answers specific to the 2006-2011 Americas Civic Si
Post Reply
Posts: 1
Joined: Tue Sep 20, 2016 9:08 pm

Lean Condition in Between Shifts and After Blipping Throttle

Post by muttrio »

Car: 2011 Civic Si
Mods: P2R TBS, KNN Typhoon V2, Q300. MAP based E-tune.

No Check Engine Light, No DTCs.

Problem: On startup (warmed/cold) with the dashboard AFR reading, I can see it drop and richen from 14.7 steadily downwards to around 12-13~ then back to lean 17-19~ then back to 14.7 ish.

In between shifts at any RPM and speed, the AFR leans out to 29.4 (as far as the sensor reads, I know) but stays there and lags for a good bit until it reaches back to 14.7. For example, if I were to drive in 3rd gear and just clutch in, it leans out to 29.4, then 2 seconds later to 17-19~ then another 2-3 seconds before it hits 14.7, but it goes below that and richens too much then back to 14.7**

When I sit parked and blip the throttle hard, car hesitates a little and does what I have stated above**. But when I blip very lightly the effects are less pronounced, like it leans out to 17-19 instead of all the way to 29.4.

WOT conditions and cruising are good.

I have cleaned the MAF, swapped the MAP, changed exhaust manifold gasket, swapped PCV, had an exhaust shop check for exhaust leaks, emissions shop saw a hose cracked off the SRI but I fixed that. I will be swapping out the primary O2 sensor, but has anyone had a problem like this?
Possible TPS or Throttle body issue?

I've searched and saw some lean problems in between shifts etc. Don't think it's a tune issue, since E-tunez has tried to correct the issue, but can't be corrected on the software side. I will be posting some datalogs and tune later today. Thank you. If I missed something let me know to clarify.
Post Reply