MPG improve chevy truck help

[abuzoz]

hello
I have chevy truck tahoe 2004 engine 5.3
I want to tune it to improve fuel economy
the car is stock no thing changed
so what you advice me to change spark, fuel....etc?
thanks in advance

[5FDP]

To be honest it's mainly down to your driving habits and things of that nature.

If you take a scan of the vehicle running through various driving situations and the fuel trims are pretty spot on, there is not much else you can do fueling wise in the calibration. Like they are within 2-4% of zero almost all the time.

If the trims are way high or way low, then you have either vacuum leaks/exhaust leaks pre o2 sensor or you have extra fuel entering the engine that wasn't requested. Like a leaking fuel pressure regulator or injector(s).

Sometimes you can optimize timing in the cruising area of the timing curve but do not expect to gain much.

For sure do a check up on the vehicle as well. Clean the MAF sensor, run good fuel, new fuel filter, spark plugs, if the primary o2 sensors are over 100k miles consider replacing them with new AC delco sensors.

[abuzoz]

Very thanks sir