Fuel Mileage

[Family Guy Diesel Ex]

Hey guys. I'm new to this forum as of tonight. My Excursion has 4" exhaust, superchip tuner, K&N Air filter. I have normally gotten 17-22 mpg and I have suddenly seen a major drop in fuel mileage. This past fill up I calculated 10.4 mpg. I haven't changed my driving patterns. The truck seems to run great. I have a little blow back around the exhaust system but I'm at a loss. I just put a treatment of Diesel Kleen in and was planning on taking it to the local Ford store for some diagnostics. Any help from you guys?

[colo86GN]

[SuperDutyPSD6L]

Possibly a fuel filter or a air filter but you would notice a change in performance with the fuel filter.

[720Deere]

Keep a close watch on the oil level. If your mileage dropped off that drastically out nowhere it could be an injector problem. It could also be a fuel leak. The 7.3 is known for fuel leaks that seem to evaporate before they are seen.

[RedneckGirl]

I have found with the ultra low sulfur diesel that my milage was suffering. I use an additive which has not only helped increase my milage but my engine is running quieter. I average 100 miles per day and spend a lot of time at the pump (I avg 19mpg). I agree with the others, check your air filter, fuel filter, and oil level (since the 7.3 has oil driven components).

Another thing, with the change in seasons milage has a tendancy to fluctuate not only due to temperature, but also due to fuel additives(anti-gel, etc.).

[whiteboystrokin]

Bought mine and the K&N air filter was clogged....was getting 10.3 Got home clean the bastard and it shot back up to 15. Try and clean it...if its clean....something isnt good.

[DA BUS]

Originally Posted by Family Guy Diesel Ex

Hey guys. I'm new to this forum as of tonight. My Excursion has 4" exhaust, superchip tuner, K&N Air filter. I have normally gotten 17-22 mpg and I have suddenly seen a major drop in fuel mileage. This past fill up I calculated 10.4 mpg. I haven't changed my driving patterns. The truck seems to run great. I have a little blow back around the exhaust system but I'm at a loss. I just put a treatment of Diesel Kleen in and was planning on taking it to the local Ford store for some diagnostics. Any help from you guys?

Welcome to FTE! I am also new.

Looking at your pic (and I really need to get one of my own to share) it seems that you're lifted. Say 6" or so? Is that a new mod since the last fill?

And / Or, did you fill it up last time at a different station that might have had water or something else in the underground tank? That happened to me recently at a T&A Truck stop in IN. The whole tank was crap and I had to run it completely out and refill it at my usual place before it ran well again. Just a thought.

[gbono2]

Throw that piece of garbage K&N filter away. They just don't live up to the advertisement. They let too many big particles get through. I got rid of mine & went to AIS. At least I know it's filtering.

[DA BUS]

Originally Posted by gbono2

Throw that piece of garbage K&N filter away. They just don't live up to the advertisement. They let too many big particles get through. I got rid of mine & went to AIS. At least I know it's filtering.

I like my S&B. What do you think of those?

[Family Guy Diesel Ex]

Thanks for the response. I used to average right around 19 as well. I had planned on getting the AFE filter and this product from Fuel Cell Premier but wanted to address the mileage issue prior to that. I just cleaned my K&N filter and am running my first dose of Diesel Kleen with the current tank I'm eating up. So far it looks like the additive may be working ok.