Help with STFT and LTFT please.

[mattspyder]

alright tuning my car with a pocketlogger software, palm III and safc II
i have 650cc, t04b vtrim turbo, 190 lph pump, plugs and wires, type s bov

k here we go, i can get the stft to 1 or 2% from 0 right,
but my ltft is stuck on -13%. now what if i set my stft to +13%
wouldnt that cancel each other out and be right on? someone please please help me im very frustrated with this

also when im doing my free revs i can hear like a exhaust backfire. like a thump, anyone know whats up with that?
PLEASE HELP

 

[CanadianTSi]

The LTFT takes along time to change. Just worry about getting your STFT to 0 and then tune the high throttle settings and your LTFT will eventually come back down.

 

[mattspyder]

ok wait, so i gotta get the low throttle settings as close to 0 as possible right, then tune the Hi throttle settings as close to zero right,
does the hi throttle settings change the stft or the ltft.

 

[CanadianTSi]

ok wait, so i gotta get the low throttle settings as close to 0 as possible right, then tune the Hi throttle settings as close to zero right,
does the hi throttle settings change the stft or the ltft.

High throttle setting are for when you're WOT. I think you're over thinking this, it isn't really that complicated and even if you're not dead on the ECU is still there doing it's job and compensating all the time.

 

[spyderturbo007]

The main reason for setting the FT's is to give the SAFC the maximum adjustment range. The SAFC allows for + or - 50%. If you FT's are off by 13%, you now have less of an adjustment range with the SAFC. Note: 1% on the ECU is not = to 1% on the SAFC, but that really doesn't matter. You LTFT will change quicker at idle. Make sure you are making these adjustments with no load on the motor, i.e at idle. Also, turn off the A/C, don't hit the brakes, or move the steering wheel.

Most people recommend trying to get the FT's between -5% and +5%.

Is your O2 voltage cycling at idle? Bad/Dead O2 sensors usual cause a FT problem. Most of the time you will have the FT max out and trigger a CEL. But, I have seen where some peoples FT's will just stay where they are.

If the O2 volts are cycling, you might want to make a 3rd gear pull and see what the O2's are doing. This might also point you in the direction of a bad O2 sensor. Sometimes you will see that the O2 looks good at idle and then drops to 0 at WOT.

Let use know what you find out.