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Fuel Milage....?

724 Views 4 Replies 4 Participants Last post by  Ranger
I have a 92 eldorado touring coupe, i am barely getting 13 mpg on the highway. the exhaust tips are black as coal...... i did change the plugs and fuel filter, air filter... i was told i may have to change the fuel pressure regulator...? any suggestions ? What should my average milage be for this car ?the engine is the 300 cu. in. thanx for any help on this.....
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A leaking FPR could be your problem - they're not too expensive to replace. A bad oxygen sensor(s) could also be your problem but they should trip the "Service Engine Soon" light. I used to get >20 MPG out of my 4.5L Coupe DeVille so your mileage does sound low.
Change your O2 sensor if you haven't done it in a while. They don't always trip a code but they do degrade. Test your FPR, the how-to is on the forum. What is your fuel pressure running?
Try running some an injector cleaner like Techron through the fuel system. Are you keeping your tires inflated properly? Is the car aligned? Everything is cumulative.
ya the car is in excellent shape, new tires, brakes , i keep a close eye on everything . i do the injector cleaner every 3 fills.i read the how to on the forum sounds simple enuf.......thanks for the input i appreciate the help
i do the injector cleaner every 3 fills.
Be careful. That stuff is pretty strong and you run a risk of destroying the pump and injector winding insulation using it that often. I never put that stuff in my tank and have yet to have a problem.
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