1991 f-150 4.9
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Joined: Jun 2022
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1991 f-150 4.9
Hello,
I am at my wits end. I have tried to have my truck repaired since Sept.2021 by four different "mechanics", even the Ford dealership mechanic. My truck has a bad miss at 1500 to 2000 rpm, bucking and jumping. Above 2000 runs pretty good but less power than before. Compression tests around 175. It idles fast around 1200 rpm. Vacuum hoses have been replaced.. Engine start sprayed around engine during idle, no detectable leaks.
Recent installs since .Sept. 2021:Throttle sensor, Map sensor, Coil pack, Complete distributor, EGR valve, EGR position sensor, Idle air control valve, Relay at distributor (pip), Computer (last mechanic reinstalled old computer, old or new engine still has miss), Air filter, Motorcraft plugs, Temperature sensor, Intake manifold gasket, Vapor cannister purge solenoid, fuel pressure regulator (old one had 20 lbs pressure, new one brought it up to 40lbs.at idle) New gas tank and fuel pump & fuel injectors installed about 2000 miles prior to present engine miss. Ok, guys & gals, I really need your mechanical wisdom. (last mechanic suspected a tooth missing from timing gear) Thank you so much
I am at my wits end. I have tried to have my truck repaired since Sept.2021 by four different "mechanics", even the Ford dealership mechanic. My truck has a bad miss at 1500 to 2000 rpm, bucking and jumping. Above 2000 runs pretty good but less power than before. Compression tests around 175. It idles fast around 1200 rpm. Vacuum hoses have been replaced.. Engine start sprayed around engine during idle, no detectable leaks.
Recent installs since .Sept. 2021:Throttle sensor, Map sensor, Coil pack, Complete distributor, EGR valve, EGR position sensor, Idle air control valve, Relay at distributor (pip), Computer (last mechanic reinstalled old computer, old or new engine still has miss), Air filter, Motorcraft plugs, Temperature sensor, Intake manifold gasket, Vapor cannister purge solenoid, fuel pressure regulator (old one had 20 lbs pressure, new one brought it up to 40lbs.at idle) New gas tank and fuel pump & fuel injectors installed about 2000 miles prior to present engine miss. Ok, guys & gals, I really need your mechanical wisdom. (last mechanic suspected a tooth missing from timing gear) Thank you so much
Last edited by Rose3371; Jun 23, 2022 at 01:48 PM. Reason: add a comment
