Okay Bad Mileage Continued After Diagnosis, and At This Point, I'm Just Open Minded on Reasons.?

[Richie]

I took it there and I got it diagnosed by 2 different places and both of them said they don't know what it could be and I'll need a tune up to find the problem ($500), the cars a MITSUBISHI ECLIPSE 1996 Manuel Base Model (NA and Not Turbo Charged). I'm getting like less than 5 miles per gallon now, and the fuel drops rapidly on full throttle and for some odd reason, the fuel seems to rise a little when I stay on low RPMs. Could it possible be the gauge itself is messed up or which part of the fuel system could this be, I wouldn't be surprised from a leak because I get smells of gas here and there, but My guess is that the fuel injectors have a problem.Adding it runs kind of hard in idle and it accelerates a bit slower than it used to on high RPMs. Where could a hard to find leak be? Any suggestions Please!!!

[larmarine83]

Yes, it definitely sounds like a fuel leak, or a clogged filter or bad pump, but more likely a leak as you say you sometimes smell gas. Whoever you have taken it to....they are stupid and they are conning you out of money. Seriously...."We have no idea what it is, but pay us $500 for a tune up and we will know whats wrong" I would have been out the door before they finished talking. You will need every inch of your fuel system check from tank to injectors, and when you find the leak, you'll need to replace that section of line. but start with changing the filter, then find a competent shop to diagnose the issue.

[peanut23536]

The fuel dropping rapidly on accel and returning up at low rpms means nothing. It's just the gas sloshing around in the tank. The only thing that matters is overall calculated MPG based on mileage. Keep in mind, unless you drive exactly the same and the same routes, results will vary. With that in mind, ethanol decreases MPG.

[TimB]

Put in new spark plugs, a new air cleaner, and 2 cans of fuel injection cleaner.

[JohnPaul]

Do this go to a gas station next to the on ramp fill up till the pump clicks off. Drive very economically onto the freeway set the automatic speed control to lets say 70 miles an hour drive 15 miles turn around and back to the sams gas station and fill at the same pump just till it clicks off. miles divided by gallons.

 Lots of things happen to a car in 12 years wear and tear compression loss? Fuel pressure test? Fuel pressure regulator leaking fuel into the intake manifold by the vacuum hose? Camshaft timing belt jump one tooth either sprocket? Timing belt put on one tooth off?  5mpg would be only 70 miles per 14 gallon tankfull. I really think you should test your mileage first (above) and it seems as if your car were actually running that much fuel there would be a check engine light too.

[miiiikeee]

it sounds like you have multi problems. 1 find the leak real quick. look for  wets spots or streaking . the area should be clean if it`s leaking good due to the fact the fuel is cleaning the area. Then do a tune up cap wires plugs fuel filter o2 sensor. when is the last time you had the timing belt changed .  a old stretched belt will through valve timing off and lead to poor mpg

[KennethS]

souinds like your fuel pressure regulator is bad.  It's a little valve located on your injector rail.  this will not only give you the smell of gas but will cause the car to consume excess fuel.  you should be able to tell just by looking at it if it's leaking.  normally it's a little round(bout the size of a half dollar) item located on the fuel rail itself..normally at one end.  Look at this and see if this isn't causing your problem.   not a difficult fix but normally around 50 bucks for that little thing.



Hope this helps