I tried the chip wired into the MAF sensor wires , it did not work I used more fuel got less power and it is now in my tool box a reminder of false advertizing and yes Virginia the engineers do know how to program the computer to get best fuel efficentcy. I adjusted my driving style and get about 39 MPG mixed driving

 

I hadn't considered the differences tht the type of tire you use can affect mpg. With my Goodyear Assurance I was averaging 30.7 mpg with mixed driving. I replaced them with some Cooper tires and my mileage dropped to 28.6 mpg. I can get a tad over 30 mpg highway where as before I was getting 34-38 mpg highway.

 

I have a 06 LS Automatic with only a drop in K&N filter.
I drive over 200 miles mixed 60% highway 40% city.
My avg has been 32-33 MPG.
When I let my daughter drive it to she gets 35+ (under 60 mph)
I average over 400 miles every tank. Yes I coast to most stops, but not much on take off (I run it fairly hard up 5,000 RPM's thru 1st & 2nd gear).
I run it full crazy mode I still get 22-24 MPG.
I was reading all these posts looking for better mileage and it looks like I'm already pretty close to the max now. I would love to get a better sounding exhaust, but only if it will help.

 

makes it worse....

 

Not necessarily so, if you go with a quality system backed with good engineering like a GMPP/Borla cat back system, or its equivalent from Magnaflow, your mileage will remain unaffected....until you get addicted to the guttural snarls issuing from under the rear bumper.

P.S..... to the forum John L 06HHR!

 

X2
Ethanol free fuel is not available around here yet but
it is on its way


Welcome aboard john

 

Yeah, tire pressure is important and so is the fuel you use. Take a look at your manual and it will tell you to use Top Tier fuel suppliers because of the additives they use. Use the wrong fuel and your performance and mpg will suffer. If you have been using other than that gas, the manual will tell you to use GM's Fuel Additive Plus. It's not cheap, but does get your injectors going again and cleans up the valves. Worked in my '10SS and my daughters 2012 Equinox that has the Ecotec engine. She was shocked when she saw the difference.

 

Anyone thought about a hydrogen intake sytem? I made one for my Cummins Ram and improved 3-5 mpg. Anyone interested, let me know and I will tell you how to build one.