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Where should I be looking if I have a LTFT number of 13 at idle and it spikes to 25 at 2500 RPM; at the same time, STFT is at zero (switching from a low negative number to a low positive number) at idle and it drops to -9 when I raise the engine RPM to 2500?
Vacuum leak? ... no because the STFT number is normal at idle when I have the most vacuum.
Fuel pressure ... no because the STFT number drops with an increase in engine RPM.
MAP sensor? ... voltage readings are within spec for various engine operating conditions.
TPS numbers are good too.
Upstream O2 sensor cycles between 2.5 & 3.2 volts (it's a Chrysler).
So, what' causing my LTFT number to go so high when I raise the engine RPM?
