Bad Gas Mileage - 13 MPG

Hello Everyone,

I'm new to this site so it's nice to meet everyone.

I own a 2004 Mitsubishi Endeavor that I've owned since new. I use to live 21 miles (highway miles) from work and was getting about 23 miles a gallon. Now that I've moved and only live 1 mile from work, i've noticed my gas mileage has dropped to only 13 miles a gallon!

Im thinking only driving 2 miles to and from work would have a negative affect on gas mileage, but could it possible be this bad????

I took it into the stealership since its still under warranty and they said they couldnt find anything wrong with it. They recommened a fuel system cleaning and a transmission flush. So of course I told them I didnt want them to do it and took it to my guy. He said the car didnt need any of the work they said.

Anyway, is their anything that it could be that is easy to overlook or is driving on average only 2 miles a day killing my mileage?

Any help would be great.Thanks!

Arroww

Your DEALERship was probably correct. Generally if something is wrong with engine management that would affect fuel economy you would get a check engine light. Driving just 2 miles to work never allows the engine to warm up and run efficiently, thus you will use more fuel. Change oil often because of water condensation build up in oil. Your exhaust system most likely will rust out sooner unless it is stainless steel. I would suggest you drive this vehicle on the highway for 20-30 miles once a week to minimize the moisture problem, it will also keep your battery charged up.

Well, A quick test would be to drive your old route once and see what mileage you get. Be sure to fill up at the same gas station and the same pump before and after. Different pumps even at the same station have a slightly different shutoff point. Park facing the same direction, and as close to the same spot as you can get. That gets as close as possible to an accurate long-term average.

Carbon buildup in the air induction system (mainly around the throttle valve and IAC valve) can cause bad gas milage. The IAC counts go up to accomodate a restricted passage, and as a result, the computer increases the fuel injector pulse width. There is a considerable margin where the computer doesn't know about problems with fuel management (or at least doesn't illuminate SES light).

You may want to read a post in this forum "how to increase your gas mileage by 50% guaranteed". At this point, I'm not willing to say with 100% certainty that it works as well as they claim. I havn't installed mine in a good vehicle yet, and didn't notice much of a difference after instalation as opposed to a week before. THe car it is installed in has some serious issues with the sensors, exhaust, and wheel bearings (and probably alignment), so that may be the cause of it not working so great.

run a proper ammount of seafoam through your fuel system.
this will clean out any carbon,moisture or whatever.
www.seafoamsales.com (http://www.seafoamsales.com) . most auto stores.

when used as directed, it works wounders.
also, any vehical driveing short trips is going to get worse millage than if your on the highway.
but the seafoam will at least clean out the fuel system.
I dont think this is your issue, but it sure wont hurt.

When you first start your car the computer goes into open loop, not reading any sensors just pours in the fuel to warm up the engine, as the motor warms it will go into closed loop and reads all sensors,maf,map and oxygen then will begin to lean out mixture according to your driving habits you will never get good fuel mileage driving short distances and is hard on the motor[carbon build up] and kills life of the oil [change more often].

I agree that MPG is probably about right for your short commute. If it's only one mile you should be able to walk it in 15 minutes and save gas that way.