1999 Ford F150

1999 FORD F-150
200,000 MILES • V8 • 4WD • AUTOMATIC
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MOSSYOAKF150
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  • 1 POST
Theirs a miss in idle, almost unnotticable and when i'm on the throttle it shakes like a misfire in one cylinder or more but i've changed the plugs and fuel filter cleaned the air intake thoroughlly with carb cleaner its like its missing but if i give it alot of gas it downshifts and runs good till it gets to a steady speed and runs at normal throttle then it shakes and acts like its missing. i was wondering if the air vacuum system could have to do with this.
Mar 2, 2010 at 8:47 PM
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RASMATAZ
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  • 75,992 POSTS
Engine running rough or misfiring can be cause by the following:
1.Defective spark plug.
2.Inadequate spark/coil,defective spark plug wire.
3.Lack of compression
4.False air leakage.
5.Faulty fuel injectors.
6.Insufficient fuel pressure.
7.Contaminated fuel.
8.EGR valve that is leaking.
9.Oxygen sensors.
Mar 2, 2010 at 9:04 PM