Hondata

Car Details:
2004 EP3
K24a swap
Injen CAI
DC 2.2 Cams
Supertech Springs/Retainers
3" Exhaust
50 degree VTC pinned at 35 degrees
DW 265c Fuel Pump
91 pump gas

Having an issue with my EP3 running lean(19:1-20:1). Had the car tuned with some new DC2.2 cams and took it to a track day, the first couple sessions it did fine, last session it started running lean, all RPMs. I thought it might be the fuel pump and just threw a new one in to see. Still had the same issue.

It's been sitting in my storage unit and I just went to take a look at it and saw the following, with logs attached, I have both the oem PRB o2 sensor along with an AEM wideband, both read similar values:

• Car would start, idle and run a normal AFR up until it warmed up to about 150 degrees

• Once it warmed up to 150 degrees I would see a lean condition, I didn't try to drive it like this so the log is just at idle

• We had it set to open loop last time we tuned it with the new DC 2.2s, so I updated to closed loop using the oem wideband, uploaded the tune and the issue went away, took the car for a drive and it was running great, around 13:1 at WOT, also logged after the issue cleaned up

• I also noticed in the Misc settings that the Speed Sensor was set to always show a speed, I switched that back to read from the stock speed sensor

I then uploaded back to open loop and issue was no longer present. I don't know if it's possible that the tune has some sort of bug in it, but I can't identify what's causing the lean condition

I attached 3 logs:

Log 1: ep3 warm up (no issue) was taken when I first started the car, AFRs looked fine
Log 2: ep3 warm up (issue) was taken after I turned the car off turned it back on and the lean condition started after ECT's hit 150
Log 3: ep3 warm up(no issue after moving to closed loop) was after I turned the car off, uploaded the same tune with closed loop enabled and the lean condition went away, although short term trims looked high at first, took for a WOT run
Tune Kal: This was your tune I downloaded after you tuned the car, didn't change anything in any tables, just the parameters I mentioned(Speed Sensor in Misc Settings and Closed Loop Operation using the PRB o2 Sensor) above when I reuploaded the tune and the issue went away.

Bump...

If the calibration uploaded to it was not right, and was corrected when changes were made to how it was setup then it sounds like the wrong calibration was uploaded to the ECU previously.

The same exact kal was re-uploaded, haven't had the issue since but I also haven't driven it a lot because it's an unregistered road race car. Does anyone see anything in the logs when the issue was occuring, log is named "ep3 warm up (issue)" when the lean condition was happening.

I dont understand log 2 you are at idle but your tps is 2% and vss 80kph constant, also you dont have iacv ?

Tuner had vss set to constant speed for some reason, it's reading 49 MPH or 78 kph, that is one thing I changed when I reuploaded the kal after I caught it. I had noticed my reverse lockout I had wired up via nitrous control was always locked, which is how I caught it.

Still seeing this issue intermittently, what other sensors help control fuel in open loop, IAT, MAP, and ECT?

Post the current calibration as wells as a datalog made showing the current issue with that calibration.

Didn't capture it due to being on a road course during a track day. Same symptoms as the previous issue with logs attached, AFR all of a sudden spikes between 17:1-19:1, when I pulled off the track I looked at my Fuel Pressure gauge and it was reading right under 50 PSI.

We need the current calibration and a datalog made using it showing the issue you are having now.