low power and bad fuel milage

MoneyWellWasted · Jul 19, 2012

i got a customer come to me his 96 f350 appartently doesnt have very much power and very bad fuel mileage. he says hes only getting bout 10 mpg empty n 5ish pullin empty 20 ft livestock trailer and also cant pull any hill more than 50 mph with the trailer. turbos good nothing shows up on the scanner, no smoke, 40-50 psi fuel pressure at idle. im stumped any ideas?

MossBack · Jul 19, 2012

Fuel filter , air filter , age and condition of oil. I'd examine trans fluid tcase and front and rear end. To start then I would I'd watch fuel and map pressure while driving and check for exhaust leaks boost leaks. Icp and dc of hpo system.

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MoneyWellWasted · Jul 19, 2012

fuel n air filters good oil apparently not very old. no drive pressure leaks. i didnt have enough time to drive yet tho. forgot that it does have slight hiccup around 2000 rpm but goes away in upper rpm n its not there under 15-1700 ish rpm

old man dave · Jul 20, 2012

Check MAP sensor line to see if there are any cracks in the hose or is disconnected. Also try running with MAP sensor unplugged, if it runs better then MAP sensor is bad.

85_305 · Oct 23, 2012

Check the FPR screen... I bet its filthy. Run a high concentrate of DK thru it or even seafoam thru the bowl.

SPEEDDEMON31176 · Oct 23, 2012

Check for leaks in the up pipes, check the fpr screen as mentioned, the fuel pump is definitely weak. You should be seeing right around 60 psi at idle not 40-50.