I have a 2000 Silverado 1500 with an intake and exhaust. There isn't much back pressure from the exhaust. I only get like 12 miles to the gallon, it's running RICH. I talked to a company NEAD about tuning it and he told me that you can't make adjustments to your factory ECU. Is this true? I always thought you can make adjustments on air/fuel, tire size, ect, ect. Does anyone have any advice about how to get my pickup tuned? Any help would be great thanks.

 

If what he said is true i dont know how i tuned mine for the turbo or 6L...

There is alot you can do man..

i have a 2000 silverado with a 6.0 and i can get 23mpg out of mine..

start with cleaning your MAF

 

I have a 2000 as well. I have messed with a few things as well. Yeah clean the MAF, maybe replace front o2 sensors, seafoam the intake, injector cleaning. Where are you located?