im surprised no one has stated the obvious here.

Every time winter rolls around (and im considering NY winters, temperature plummet and gas consumption increases , lowering the mpg also)

In summer youll get 80-90 (or 85-95 per quarter tank as OP has mentioned) in winters its around 70 (i.e 220-240 miles on an entire tank of gas depending on the severity of winters in your area)


There's nothing wrong with your car; our cars aren't the most fuel economical vehicles out there but thats not why we bought them.

False I get 200 miles to a tank (15-16 mpg) regardless of time of year, fuel grade, or driving style

Then your car needs to be looked at, if its stock that is.

Im getting higher mpg in -25C weather up here right now.

The reason I had started this thred was due to the fact that winter weather hadn't yet set in, it was cooler, but never below 40-45 degrees when I was driving. Now I can contribute the lack of MPG to the cold/snow/road conditions and what is probably 10% ethanol in my gas here in NY.

Service maintenance? Drive smartly is the best way to save gas ^^

My mileage has been getting shittier and shittier per fill up, i think i need a tune up soon.

Change the spark plugs etc.

Im only at 275 KM and i only have 3 bars left...

Update: I just tighten the plenum bolts and come to find out that only the number 1 bolt was REAL loose. I don't think that is going to solve my problem. I guess I should change the spark plugs/wires and clean my R2C air filter.

Anyone know any good plugs and wire for our cars?

We don't have wires. It's Coil on Plug ignition.


I just used the OEM plugs when i changed mine. I swapped them at around 110K miles and gained 1MPG. They weren't really all that bad looking.

So I guess that's not going to help me either, but I guess it would not hurt if I change them. I only have like 76K miles on the car.. I gotta find out why my gas mileage as dropped so dramatic.

Has anyone actually had success with MAF cleaner & new PCV valve? I get 20 mpg using 87 octane with 80% hwy 20% city (2003 5AT).

Several mentioned that using lower octane fuel retards timing - does resetting the ECU fix this? What does resetting the ECU do in general?

Today I'm about to switch over to full synthetic, synthetic diff fluid, drain and fill the trans with fresh fluid, and replace the pcv valve. Next week ill be going back to stock 18s instead of 20s. And changing my plugs to hopefully increase my mpg. I also seafoamed last week...stay tuned lol

There's your problem. Your odometer is reading 10% low. Plus the 20's give you taller gearing so you have to push the peddle harder to get the same accelleration.

Just wondering how you decided that without knowing the circumference of his tires?

So I have been 'lucky' enough to find a chain gas station that offers ethanol FREE(!) 91 octane fuel. Hopefully this will restore some of my lost MPG until spring rolls around and the temperatures rise again.

After switching to full synthetic, fresh diff fluid, fresh trans fluid, seafoam, and a new pcv valve....my gas mileage is at an all time low 12.7 mpg today