Drop in mpg
My truck is a 2005 Chevrolet 1500 crew cab with 5.3L engine, auto trans, and 3.73 rear end.
From day one, I got over 19 mpg solo at mostly highway speeds.
Recently the mpg has dropped to the high 16's and low 17's.
It seems to run as well as it always has, no missing or sputtering.
The air filter has been checked and is ok. My mechanic says the fuel filter is in the gas tank and does not require service.
I have heard everything from a lazy oxygen sensor to the MAF maybe needing cleaned.
Does anyone have any ideas?