Hey guys,

Has anyone else been getting real chitty gas mileage lately? I've tried different gas stations but its still chitty. I figured the oxygenated fuel is causing my problem, but I'm down to 8 or so miles per around town. I was getting about 13 and 15 to 16 on the highway? Any thoughts? Maybe o2's or something?

 

That a little excessive I think. I usually lose 2-3 MPG (summer I get from 13-14, winter I get 11-12)

Is the truck running like usual?

 

check your air filter. My filter got wet by sucking up snow. A clogged filter will cause bad fuel miliage.

 

The truck is running ok, there is a loss of power. The air cleaner is not dirty or wet. The fuel filter was changed about 5 months ago. Any other suggestions?

 

How about cleaning the mass airflow sensor and the throttle body?

 

Have you checked the air pressure in your tires lately?

 

Trust me, driving in the winter months is going to be a huge difference. I drive in Wisconsin winters and the gas mileage drops off big time. In summer, I can average 17-18 mpg. From November-April, I get around 13. Driving the same roads at the same speeds. I've heard you loose between 15-20% mileage in winter.

 

throttle body is clean, maf haven't cleaned yet, new tires with correct pressure. Was getting good mileage with new tires in the fall. So I know it's not the tires. With the oxygenated fuel, do you lose power along with mileage? What about O2's. My truck has about 139k with the original O2's.
Mike

 

A little off-subject, although I am getting crappy mileage right now too, I believe it is the winter months also, heard that for years. Anyways, pstmn1, how do you like your exhaust setup? I have that same exhaust setup going on next week but with 3.5" tips. Also, how the hell do I get that signature to show up on my posts?? I can't figure that out. Sorry if I hijack your post, didn't mean to.

 

Miles,
Absolutely love my mags. Had I to do all over again, I may have gone with the 3.5 slash cut tips. Your gonna love it. The tips I find make the exhaust burble alittle more under part throttle. As far as the signature, go to the sign in page and scroll down to signature and fill in the info. When done all you have to do after finishing a post is scroll down to where it says show signature and check the box and hit enter.

 

In winter cold temps, the air density is greater which means more fuel must be used to maintain the same air to fuel ratio; that will consume more gas.
The cold starts are richer in fuel use.
As sensors age but still are within tolerence, this can also add to fuel use.
So far i'm doing well and can still run off 16 mpg trips in 25* temps. with a 5800 lb loaded 02 Super Crew 4.6.

 

I should note that getting 13 mpg has been with temperatures ranging from 0F, to -25F. Yes that was a negative. Towing at those temperatures, I can watch my gas gauge drop.

 

Ok,
Definitely loss of power. I used to be able to spank my buddies vortec. As a matter of fact I would get about 3 lenghts on him before the next light on this stretch of road near my home. Today he got me by about 6 lengths. I got problems. No codes yet. Need help.

 

How about a tune up??

 

Did a tune up about 4k ago. Plugs, wires, cap, rotor, ect..
This really has me stumped. I was going to get a 9100 from Mike Troyer but I have make sure the truck is running a peak performance before tweaking the programming. I would think.