Decreased Fuel Economy

[Massasoit]

I had been getting about 28-30 MPG right after I got the car back in April, but recently it has gone down to low, and by low I mean just refilling it, it got 23.28 on the last tank. I have the window sticker from the original dealership, and it says (i believe) 25 - 31 MPG.

I would really love to get the MPG back up, becasue, well... I don't have all that much money so spare, and getting back that like... Seventy miles per tank would be great.


I had the IAC, fuel filter, air filter, and I believe an O2 sensor replaced at my local mechanic, but the mileage is still the same.

Should I replace the spark plugs? I have no idea when the last time they were replaced are.

I also think I have a small oil leak - if oil were getting into the cylinders, would the mileage decrease as well?

Thanks for putting up with my car uneducatedness,
Massasoit

 

[AliasJerk]

im assuming you have a duratec (V6)

IN which case, the primary reason for performance and fuel economy loss is due to carbon build up. you can check to see if you have this issue, by removing the throttle body, if its all gunked up in the back then its time to do a UIM and LIM rebuild, which will clean all of the carbon gunk off, restore horsepower, and of course, increase fuel economy.

Also, spark plugs and wires, when really old, wreck fuel economy. Which would be a good idea to reaplce for preventative maitnence, if you dont know when they have been replaced.

 

[twocontours]

Are you sure it's not just the impact of running the A/C during a hot month. It really reduces the mileage.

 

[Massasoit]

AC is broken.

I roll with the windows down, yo!