STFT at idle really weird
 

I have rc1000cc injectors and they are scaled, but I was wondering why my STFT at idle acts up.

i drove to my tuners house and when we logged the car as soon as i pulled up the car seemed fine, driving fuel trims i believe were at -6% and and idle trim was at -8% . I brought it to him since i was getting the p0171 which was triggered by the weird symptoms.

after letting the car idle the STFT would be fine and cycle then all of a sudden shoot up to -20% and would raise the fuel trims.... but it would also go all the way up to -25% really quick then go to 0. sometimes it would stay at -25% and eventually go down but we sat there for possibly 20min idling the car and i believe the code came on once or twice.

can anyone think of what can be a problem? my previous tune was really messed up and probably a month and a half before i received this tune i installed an o2 housing with a used o2 sensor. can it be the sensor going bad or the injectors? the injectors are possibly 2 yrs old bought brand new and i believe were at 50-60% idc on the previous tune.

anyone have any input?

no one knows? :/

What do the LTFT's say?

ltft's r fine. they stay within the same range, unlike the STFT's how they go out of wack if it idles for too long or no gas is being applied.

If even the long terms are that far negative, it's still running rich. It seems to me like you need to adjust the scaling and latencies. This is the best way I've read how to do it (from l2r99gst);

1. Choose a global setting (ECUFlash injector scaling number)
2. Log trims at idle and cruise
3. If trims are roughly the same, but positive, then you need to increase your global fueling, or in terms of ECUFlash, you need to lower your injector scaling number.
4. If both trims are roughly the same, but negative, then you need to descrease your global fueling, or in terms of ECUFlash, you need to raise your injector scaling number.
5. If idle trim is more positive than cruise trim, then you need to increase the dead time, or in terms of ECUFlash, you need to increase the latency value.
6. If the idle trim is less positive than the cruise trim, you need to decrease the deadtime, or in terms of ECUFlash, you need to decrease the latency value.

Note: After #5 or #6, you may need to readjust #1 accordingly.

Post#69
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