I installed a UTEC and was working with it, but I kept noticing over 6K the car feels like it loses a good bit of power. I did an AFR log with Cipher and noticed the banks over 6K do not match. Any suggestions on what to do about this?




edit: I did some more log runs, tried resetting the ECU and disabling the UTEC and it still does it, but with the UTEC off the banks are reversed (wtf?).
This really sucks. I have **** for power over 5700 RPM. My midrange is very strong, then I hit just past 5700 and the power takes a big crap, and the higher it revs the worse it gets.

Does anyone have any ideas?

 

Bad injector?

 

I hope not... its a 2005 with 9200 miles on it.

 

Here's my 2 cents from a scientist's standpoint:

did you only do 1 experiment? You cannot prove that the AFRs are statistically significantly different unless you have done several experiments.

 

You might like to see this thread on g35driver forum about AFR B1 vs B2 discrepancy.
On my car, AFR on B2 is almost always higher. I even swapped sensors to eliminate calibration issue.

I read UTEC manual but I don’t remember seeing if it can control injectors separately?

 

Ok, that's good to know then. Any idea why I lose so much power over 5700 RPM? I've tried no UTEC (map 0), using "ECU" in timing/fuel maps over 5750 in the UTEC, and my own tune, and they all do it.

I have all the UTECs settings about what the default parameters are, short of the revlimit, which is set to 70 (instead of 72 or whatever it was at).

 

Disclamer: I have no clue …

Kiamo, log your timing and cams and injectors pulse and see what you have above 5700 RPM.
Does UTEC shows any knocking? Do you have any intake mods? What year is your car?

 

Timing is fine, and my UTEC settings are actually ever so slightly less agressive over 5700 RPM. Injector pulse looks normal, raising slighly over the RPM range.
UTEC is showing no knocking, timing isn't being pulled (which is almost what it feels like, though). I have JWT intake, Crawford upper plenum, headers, test pipes. The car is a 2005 Enthusiast.

edit: injector pulses are virtually identical on both banks through the rev range. At 2500 RPM, its around 12.2, rising to 15.8 by 6500 RPM, pretty linearly.