GX460 fuel trim bank 1 and 2 mismatch

[tingc222]

So I’ve been eyeing closely the fuel trim numbers in my 90k mile 2014 GX460 on OBDLink. Truck drives with no issue and no codes are triggering for me.

At idle (550-700rpm):

LTFT Bank 1 +3.1%
LTFT Bank 2 +0.8%

At 1500-2500 rpm:

LTFT Bank 1 +2.3%
LTFT Bank 2 +3.1%

STFT appears to fluctuate normally, within +/-5% of 0 at all times. O2 sensor and MAF sensor ranges appear to be reporting reasonably.

I dumped some fuel system cleaner in the tank about 3 tanks ago. Not sure if that did much for me.

some sources say that LTFT within +/-10% of 0 is essentially normal. I just didn’t expect a Bank 1 vs 2 mismatch.

Any thoughts? Thanks..

 

[Rednexus]

I probably would not worry about it. Your LFTTs are pretty low and close to 0. It might be a slight side-to-side difference in the upstream O2 sensors. If you are curious, swap the upstream O2 sensors from left to right and see if the LTFTs reverse themselves. It also could be carbon buildup on valves on one side of the other that could be cleaned up with some Seafoam, or maybe your spark plugs are near the end of their lives.

FYI my GX470 is usually ~3% different side-to-side but at around +8-10%. I have a CAI on mine so the LTFTs are a bit higher than stock. Staring at LTFT's too much will drive you crazy .