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Your fuel trims look very similar to mine. I'd say you have the 30lbers. Anyway, its more important to keep your STFT closer to 0%, rather than the LTFT. The ECU uses STFT to insantly compensate and adjust your A/F ratio per readings from the o2 sensor. I notice when i go WOT or into open loop, both my trims go to 0 %, as this is when i know i am in open loop. In open loop, fuel trims are meaningless, since the ECU is running the engine off of pre-programmed fuel maps. In closed loop, the ECU is adjusting A/F ratio off of the o2, which is what you look at in fuel trims. The only time you will get a too rich CEL, is when BOTH your STFT and LTFT are maxxed out at -25%. This is telling you that the ECU has absolutly NO room left to shorten the injector pulse width(fuel spray out the injector). If you have a -15% STFT, this doesnt mean you are running rich at all, it just means that the ECU is trying to trim 15% of fuel to keep the engine running the optimum A/F ratio. This is why you typicaly want to keep STFT as close to 0,because this give the ECU its greatest room for intantaneous fuel adjustment( +25 to -25%). Running larger than stock injects, it will be very difficult to get LTFT close to 0. In order to do this, you need to get your STFT's to go into the lower positive #'s for a bit. STFT is telling you waht the ECU is instantly adjusting, and LTFT is telling you what the ECU has been doing over a greater amout of time. If you want to lower your STFT's, then lower your fuel pressure a tad bit. Just by lowering several psi, that can lower trim #'s by a few numbers. If you can get the STFT to get into the lower positives as you drive around, then that will start to bring down the LTFT #'s. Even with normal stock injects, the STFT will fluctuate in the postives and negatives, but it will be around +7% to -7% or around there.  13.5 @108 MPH-2.2 60ft(stupid FWD!) S16G @ 18 PSI/FMIC/Running on MegaSquirt II (Now with sequential fuel injection) My webpage: http://eclipsed4evr.home.comcast.net -1998 Mitsubishi Eclipse RS-T- "Toy" -1992 Plymouth Laser Turbo AWD(SOLD) -2000 Honda CR-V(daily)
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