Extremely poor gas mileage on Mitsubishi endeavor.. Its killing us having to refill this thing.. Whats wrong?

(2010-05-29 15:56:48)

1. Candymancan21 Says: My mom has a mitsubishi endeavor 2004. It's getting terrible gas mileage. I filed it up yesturday, she drove it around 54 miles today and the is already down 1/4 a little more in fact . The tank is 21 gallons. So tha would be about 6 gallons used, 54 divided by 6 is 9 mpg. The worst part is she drove on the freeway so the mpg should be much much higher. We drove about 13 miles in the city today and the dial went down noticably about half way from a quarter of a tank around 2 gallons. So we got like 6 mpg

why is this thing sucking gas we can't afford this cause the thing needs 93 premium otherwise the engine ticks.
15 hours ago - 3 days left to answer

2. goldwing127959 Says: Have the fuel pressure checked.Have the fuel pressure regulator is supplying to much fuel, it will do this. Also When was the last time you changed the plugs, If the plugs are old, and misfiring, it to will effect mileage. How about the air filter, if it is dirty it to will make it suck more fuel then needed.

3. Old Man Dirt Says: The first thing to realize is that it is an Endeavor and will never get great mileage.
That said, give it a tune up. Being a 2004 there is a good chance that it has over 50000 miles on it and needs new spark plugs. Don't forget to check out the air filter as cheap as they are just put a new on in. If it has spark plug wires and a distributor replace the parts there too.

4. Bella Rina Says: I thought you were in terrible trouble and wanted to run away?