Hi everyone, my name is Nick, from Denmark and a happy owner of a very modified Peugeot 207 RC which has the same engine as the Mini Cooper s R56 (N14).
I have an issue with it as when im changing gears (manual transmission) the afr readings will show lean for a couple of seconds, then go back to the correct afr numbers. It does not matter if its on or off boost, same problem. When driving in gear and on/off boost afr readings is as it should be, this problem only accours at gear change.
I am wondering if this could be tuning related or a mechanical failure?
I have tried changing out the pre cat O2 sensor and reset the ECU values which seemed to help for a short period of time, but the problem came back after a day or two.
the engine is built, running a Garrett GTX3071R with tial external wastegate, bigger inejctors, cams, snowperformance methanol port injection and etuners stage 4 tune.
Has any of you come across an issue like this before I would love to get some inputs as to where to start diagnosing this.
Link is a video of the problem.