CowboyBilly9Mile
Charter Member
Vehicle desc is in the signature (and vehicle uses MAF) and presents no drivability, fuel consumption, performance or any other concerns. I got curious awhile back and pulled fuel trims and voltages on the upstream O2 sensors; the results are below. This data was taken on a fully warmed up engine, vehicle parked and revved to ~2,000RPM. However, the results are usually the same at idle and at cruise, 65MPH and ~2,300 RPM. I say usually because, there was one event at idle where the LTFT's hovered around +3%, and why that one time I cannot explain.
Here's my concern/thoughts/opinions....LTFT's should be close to (ideally) zero, despite vehicle aging, and as seen are adding fuel. It is also noted that whatever be the cause is affecting both banks equally, and to the point that if there is a variance between them, it's not readily seen. Varying engine speed doesn't affect LTFT's, thus and IMO lessening the likelyhood of a VAC leak (including EGR valve not fully seating). MAF sensor was cleaned maybe three years ago and has ~28K miles since then. I have NOT checked fuel pressure; I do make it a point to always run top tier fuel. Fuel filter (thinking volume here) is new, yet not near replacement time (and vehicle doesn't starve for fuel when floored and held on a highway, it revs freely ~5,500RPM then hits the next gear). Whatever it is equally affects both banks, thus ruling out some things. On the flipside, it's approaching the "off by 10% flag" too (but I don't have a LTFT history over the years either), and this bugs me.
Your thoughts? I ask because, it's half apart now and although I have my doubts I could replace the intake gasket. I just have my doubts that this will change anything.
Edit: FWIW I do have FORScan, thus giving me the ability to pull the extended PID's.
Here's my concern/thoughts/opinions....LTFT's should be close to (ideally) zero, despite vehicle aging, and as seen are adding fuel. It is also noted that whatever be the cause is affecting both banks equally, and to the point that if there is a variance between them, it's not readily seen. Varying engine speed doesn't affect LTFT's, thus and IMO lessening the likelyhood of a VAC leak (including EGR valve not fully seating). MAF sensor was cleaned maybe three years ago and has ~28K miles since then. I have NOT checked fuel pressure; I do make it a point to always run top tier fuel. Fuel filter (thinking volume here) is new, yet not near replacement time (and vehicle doesn't starve for fuel when floored and held on a highway, it revs freely ~5,500RPM then hits the next gear). Whatever it is equally affects both banks, thus ruling out some things. On the flipside, it's approaching the "off by 10% flag" too (but I don't have a LTFT history over the years either), and this bugs me.
Your thoughts? I ask because, it's half apart now and although I have my doubts I could replace the intake gasket. I just have my doubts that this will change anything.
Edit: FWIW I do have FORScan, thus giving me the ability to pull the extended PID's.
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