Wednesday, August 27, 2008

Understanding Long Term Fuel Trim

Well, with Hotrod's guidance, I have a much better understanding about what I'm seeing with LTFT on the Scangauge.

When cruising, I am seeing a steady LTFT at 17. With almost 40% ethanol in the tank, that seems a little high. Maybe I'd expect more like 13.


Anonymous said...

Buzz- I captured 45 frames of E30.6 data running in my '04 Saab 2T Aero. Looks like LTFT were running at an average of 9.3 at 69-70mph on level ground. Was that your experience also at that % alcohol?

I did note that going from E20 to E30 the boost will not "peg out"- instead it acts more like it does on premium NL- it would barely encroach the red zone and quickly dump back to safe. Wondering if that is due to nearing LTFT limits?

I am next going to log it on premium NL 93. After that I will do the E20 log. Can one post this here as a file? What format?


buzzcut said...

Al, at roughly E40, I'm seeing LTFT of around 17.