WebDec 24, 2008 · LTFT Max Negative Value. In good engineering practice, what would be the most negative value LTFT one would run? i.e. is -10 to -4 acceptable? ( (The issue, friend … WebMar 19, 2024 · The LTFT is positive but the STFT are negative and it may not have had enough run time to bring the LTFT back down. Verify fuel pressure too. At idle, with the FPR vacuum line unhooked and with the engine under load. Make sure it's within spec. 2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
Long-Term Fuel Trim High at Idle: Causes and Fixes
WebMar 30, 2024 · LTFT-B2-30.4% The B2 LTFT is always high, unless I nail the throttle, then it drops for only a moment. What does this indicate? At 2000 and 3000 rpms, the reading differences are similar, but lower. STFT-B1- negative 0.7% LTFT-B1-7.8% STFT-B2-0% LTFT-B2-22.6% Air filter is clean, Airflow sensor is clean, O2 Sensors B1-S1 and B1-S2 both give ... WebFeb 23, 2024 · LTFT is a learned value that has the purpose of keeping the STFT as close to zero as possible. With that level of negative fuel trim, I would look at a defective fuel regulator diaphragm for example Have a look at this article Gears Magazine Put Fuel Trim to Work for You It makes it a little clearer Hope this helps Ravy96 Registered diane setterfield facebook
Very High Negative Fuel Trims - CivicX.com
WebNov 16, 2024 · keith November 16, 2024, 7:31pm 7. The long term fuel trim is comparing the actual fuel trim (fuel pressure x duration of the pulse) to a table of theoretical values stored on a table in the computer that was derived from the engineers at the manufacturer. The actual fuel delivery during closed loop (engine warm) is determined by the O2 sensors ... WebJan 26, 2024 · If the value is negative, it indicates that the ECU is decreasing the flow of fuel into the injectors because the data it sees shows that the air-fuel mixture is too rich. What … WebJul 9, 2013 · Running too rich – High negative fuel trim corrections can be caused by MAF sensor problems, high fuel pressure, leaking fuel pressure regulator diaphragm, faulty … dianes farmhouse