MPG increase help

[dabeech]

I have a 07 Yukon XL 2500. Only getting 10 mpg. Put in new plugs and air filter. Still seems to have a slight hesitation at idle. Clogged fuel injector? Wife drives the rig and she drives like grandma. Did some hwy driving and still only 10 mpg. Suggestions?

 

[mikeb33]

Mostly around town and much "spirited" driving, I get an average of 12.5.

 

[Conor]

10mpg is pretty low. Have you tried cleaning the throttle body? How many miles?

 

[rogersinsel]

I have a 07 Yukon XL 2500. Only getting 10 mpg. Put in new plugs and air filter. Still seems to have a slight hesitation at idle. Clogged fuel injector? Wife drives the rig and she drives like grandma. Did some hwy driving and still only 10 mpg. Suggestions?

Is it completely stock?

---------- Post added at 11:22 AM ---------- Previous post was at 11:19 AM ----------

I have a 07 Yukon XL 2500. Only getting 10 mpg. Put in new plugs and air filter. Still seems to have a slight hesitation at idle. Clogged fuel injector? Wife drives the rig and she drives like grandma. Did some hwy driving and still only 10 mpg. Suggestions?

14 city- 18 highway is sticker mpg. 4wd.

 

[dabeech]

Is it completely stock?

---------- Post added at 11:22 AM ---------- Previous post was at 11:19 AM ----------



14 city- 18 highway is sticker mpg. 4wd.

Yes, all stock. Just put some new plugs and air filter in. It only has 54k miles on the truck. Mostly around town driving, but even when I go on a long hwy drive it's only 10 mpg.

---------- Post added at 12:03 PM ---------- Previous post was at 12:02 PM ----------

10mpg is pretty low. Have you tried cleaning the throttle body? How many miles?

Never tried top clean the throttle body. Is it hard or a quick weekend project?

 

[Mr. B]

Try running a few fuel injector cleaner bottles through it.

Maybe a bad O2 sensor. That can cause a big mileage drop.

 

[Conor]

Yes, all stock. Just put some new plugs and air filter in. It only has 54k miles on the truck. Mostly around town driving, but even when I go on a long hwy drive it's only 10 mpg.

---------- Post added at 12:03 PM ---------- Previous post was at 12:02 PM ----------



Never tried top clean the throttle body. Is it hard or a quick weekend project?

Yes it is easy and can't hurt. A bottle of Lucas Oil fuel injection cleaner couldnt hurt either. Also, make sure your tire pressure is where it is supposed to be. I run mine around 5 lbs below max psi to get the best mpg possible. The harder the tire is the less rolling resistance it will have. Just be carefull not to over fill, and also keep in mind that a warm tire will read about 5lbs more pressure than a cold tire.

 

[dabeech]

I called the GMC dealership. They said that the check engine light would come on if it was a bad o2 sensor.

---------- Post added at 12:59 PM ---------- Previous post was at 12:58 PM ----------

Any online instructions to show how to clean the throttle body out?

 

[young_2010_chris]

I called the GMC dealership. They said that the check engine light would come on if it was a bad o2 sensor.

---------- Post added at 12:59 PM ---------- Previous post was at 12:58 PM ----------

Any online instructions to show how to clean the throttle body out?

does it have a 6.0?

mite need to change coil packs and wires to im sure it wouldnt hurt

 

[dabeech]

yes it's a 6.0L. Changed the plugs, but not the coil packs and wires