WebDec 4, 2024 · When descending a hill in a lower gear where the engine is revving a little high as the engine is doing some braking, the LTFT drops to maybe %5. I would think a vacuum leak would produce even higher fuel trim during this condition. Both the MAF and O2 sensors are old. I'll probably just replace them both. 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 ...
What Should Long Term And Short Term Fuel Trim Be? The Drive
WebOct 23, 2024 · Negative LTFT should produce running rich codes with stock calibrations. Fuel pressure seem high, 55psi at idle, measure vacuum at pressure regulator. Compare with another intake manifold source. ... High negative ltft's. By kissmyss in forum 3.8L V6 Supercharged (L67)(L32) Replies: 10 Last Post: 08-05-2024, 05:02 PM. WebThis can cause hard/no starts as well, but usually results in a rich running condition (fuel trims in the negatives).. but still it's worth checking out. Remove the vacuum hose for the regulator and smell it. If you smell any fuel vapors at all, this is leaking and needs to be replaced.. (likewise if liquid fuel comes out of the hose). lithia tri cities cjd
Long term fuel trim - Ricks Free Auto Repair Advice
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 ... WebAug 18, 2015 · STFT usually cycles rich to lean similar to the voltages generated by the upstream O2s. So if your numbers are STFT that are about maximum of the negative side, they are OK. So in retreading your post I'll assume the numbers are LTFT. I'd check the fuel pressure to make sure it is in spec-about 50psi (3.5 Bar) at idle. WebAug 26, 2016 · HolyToledo. I replaced every single rubber tube, plugs, ccv, disa, all the usual stuff, and still had high multiplicative fuel trim on inpa at around +10 on both banks. I had fixed all the vacuum leaks, so I started looking more closely at o2 sensors and maf. At idle, short term fuel trim was negative, and on throttle, it went positive, to ... improve english text online insta