I know this is an issue that has been beaten to death in this forums, and searching past threads didn't give me a solution.

My 96 GXE (auto) gets around 20-21 MPG in the city which I believe is good considering most of my trips are short and very little highway. But this weekend before taking a longer trip, I filled up and when I got back last evening filled up again to a get a better indication of highway gas mileage. Guess what? only got 23.7 MPG. About 90% of this trip was at steady 70-80 MPH with no traffic.

I have checked the ECU for knock-sensor codes a few days ago and didn't find any. I use premium gas and checked my tire pressures before I left. The Air Filter is also new. What could possibly be giving me such bad mileage on the highway?

 

anybody....?

 

Chillax - my car is in near perfect condition and I got 21mpg on my last tank and it was almost all freeway, 70-100... "EPA estimates" for highway are 4th gear 2000rpm all the way, not something you'd be likely to achieve... Try driving 55 the whole way next time and it may improve

 

Can anyone tell me if a clogged fuel-filter can reduce gas mileage? I've heard this discussed in old threads - but there wasn't a conclusive answer if a bad fuel filter reduces gas mileage.

Thanks..

 

Seems to me a clogged fuel filter wouldn't really affect milage as much as it would affect performance. I don't think you would be traveling 80mph with a clogged filter without the car cutting out & maybe setting your service engine light on and off. If unsure, you should just change it out for grins. It's not that expensive or time consuming and it'll be one less thing to worry about.