My GSR now has about 195,000 miles on it. Since I got the car from my dad at 165,000 I went from averaging 32 mpg highway, to about 22 highway now. My around town mileage sucks. All the routine maintenance has been done, the car hasn't been abused, and it's just been gradually decreasing over the past 6 months... I'm assuming with this kind of mileage that my piston rings are shot, I burn a quart of 10w30 every 2,000 miles or so. Would poor compression cause my mileage to dip like this? If now, what would?

Thanks in advance,

-Sean-

 

yeap thats a cause for poor mileage.
stressing the engine...
well now crack it open and upgrade!!

 

the quick answer to your question is YES

 

Thanks for the quick responses guys... but do you think bad compression can cause a 10 mpg drop? That's a sh*tload...

 

Try looking for worn ignition components. I found that a worn cap and rotor can cause really bad gas mileage. You might also want to replace the o2 sensor. Your cat could be clogged, or some other exhaust or intake component.

If your engine was worn enough to cause that kind of decrease in efficiency, I would think that bad gas mileage would not have been your first tip off that the engine was that worn. This is probably nothing too serious.

 

a quart every 2000 is actually average. even factory specs say 1qt every 1000 is normal even though we all know thats BS. I burn about a quart every 2000-2500 too, but thats with 10w40 non-syn. when i was on 5w30 syn, it was like 900-1000 miles per qt.

my compression was about 170-175 across the board when i had it checked. My mileage is still pretty good though...sorry hope that helped.