So Ive been doing a lot of highway driving (usual around 60-65 mph) and Ive been finding that H3 has been using a lot more fuel than normal.

I filled up (had a bit under quarter tank) and I put in 70 litres (18.42 gallon). I check the mileage (I reset it every time) and it was 215 miles. By my calculation that is just around 11 mpg.

That cant be right. I remember I used to get a bit over 20 mpg. Or did i just dream that.

I did a search and noticed a few posts that are related to engine head. I got 39000 miles on it, and its an 06 (one of the troubled head ones), but I am not showing any head issues at this point.

The only mod is that I put in K&N filter.

Suggestions?

Marko

 

Not every time, but almost always if you have the head valve issue you would have a CEL and you would notice a very rough idle.

Heve you checked your brakes? A stiff corroded caliper could drag a pad and would pull down your MPG.

You might have been dreaming about 20mpg, at the 65 mph range I can get 19 in warm weather. Today it is 15F now and 19 is not gonna happen in that.

 

interesting idea. Would I notice drag or brake pads burning off?

Pretty sad gas mileage for a 5 cylinder.

 

My 06 gets the same... NEVER have i gotten more than 11mpg highway and or city. I have a k&n CAI too... havent noticed a difference in mpg. Mine had the head issue too.

class action lawsuit or wut?

 

Both.

There will be days when the weather sucks: cold blustery wind head on, and driving conditions are not ideal: many large hills, etc... when we get less than stellar mpg, but you should be doing better than 11-12 for sure at 60-70MPH.

 

I can drive with normal tires (285/75/16) around 280miles on a fuel tank till the light with low fuel come up and around 260 with Toyo M/T 315/75/16.
I don't know if it's good or bad, and I have the 06 with 30000k.

 

I gave up with the whole milage thing. I'm driving a vehicle with the aerodynamic properties of a 4x8 sheet of plywood with a weak 5 cylinder engine - good milage ain't gonna happen!! My 4.4 BMW X5 is the same - huge performance engine with not the best aero package! If I wanted good milage and it was a real concern I wouldn't have bought these vehicles. That being said - I bought these cars for their performance, looks, and comfort - I wouldn't get rid of either one!

 

aerodynamic or not, 11mph seems way too low for me, especially as many of us are getting 16-17mph on average. That's even way below GM rating. If you are doing the same type of driving as when you were getting the better mileage before, then there is something definitely wrong there. I just put in a green filter in this weekend, I wonder if that will influence the mileage at all.

 

Actually the K&N filter should have helped you a bit. I get around 17+mpg.

 

wouldnt you get better gas milage in cold weather? engine runs cooler, air is cooler and more dense,ect..?


but 11 mpg is not right, i get 17 consistantly every tank, no matter where i drive

and i have '06 with the 33's