Engine Performance problem
1993 Ford F150 V8 Two Wheel Drive Automatic 122000 miles
My 93 F150 has a 5.0 with AOD. I bought it in 1995 and was getting 16-17 MPG consistently in town. Now I barely get 10 MPG city or hiway. I had to replace both fuel pumps because when I ran off the front tank fuel would return to rear tank and pressurize the rear tank. I've replaced plugs, wires, rotor, dist. Cap, PCM, fuel pressure reg, catalytic conv, all fuel injectors, O2 sensor, and more. It doesn't use any oil, if the motor was shot I would expect oil consumption. After replacing the O2 sensor, I can drive 200 miles and it will blacken it so it is running VERY rich. The exhaust system was very black. I live in a city with 5,000 ft elevation and pull 19 on a vac gage, so I don't think there's any vacuum leak. The computer doesn't set any codes. Base timing is normal. Trans. Is working normally, brakes are fine. Shops in town tell me 10 MPG is "normal". A 40% drop in gas mileage is NOT "normal". What could be wrong, faulty ignition?
have the same problem?
Friday, April 17th, 2009 AT 10:08 PM