Worse gas mileage after install

[UnderDawg]

I have a 1999 GMC Yukon 5.7. I was averaging about 14½ mpg, about 90% city driving. I installed an AirRaid throttle body spacer, an AirRaid intake system and a 160 degree thrmostat. Two tanks full of gas later, I'm getting about 12 mpg. All the claims show that these accessories should have improved mialeage, but I have experiences the exact opposite. Driving habbits are the same. So why did my mileage get worse?

[GM-Tech]

So why did my mileage get worse?

 

<{POST_SNAPBACK}>

 

 

 

Because you got taken.

 

There is no magic pill for gas mileage. You think GM wouldn't put a simple spacer in if it would increase gas mileage? And the hotter you can run an engine, the cleaner and more efficient it will run.

 

The absolute best way to improve your mileage is to improve your driving habits. Drive like there's an egg between your foot and the gas pedal and you don't want to break it.

 

Oh, and take off all those gadgets you put on.