woodsboy

I have a 2000 Ford F-150 4.6 V-8 that has a shake that starts around 40 mph and continues. You can gas it out, but it returns smaller and less noticable around 65 mph. Around Thanksgiving of '09 we ran a diagnostic and it said valve 4 and 6 misfire. Also said the egr was having problems. Have replaced all the spark plugs and ignition coils. HELP!!!

KStromberg

So, have you addressed the EGR issue?

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-1992 Ford F-150 (winter truck)
-1998 Lincoln Mark VIII LSC (fun car)13.591@101.72mph

Bert

Does the shake feel like an engine miss or something in the drivetrain? The u-joints can do that except at a faster vibration.

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Bert

woodsboy

No, I have not adressed the EGR issue yet, for the simple fact that I was told it might not be this. And to answer rtg143 it feels like its coming from the engine not really the drivetrain. Its also weak on power for a v-8 it will range from acting like a weak butt 4 banger to a stout v-6. Could the EGR be doing this?

KStromberg

The only reason I questioned you there was because in your first post you made it sound as if the EGR issue was in addition to the misifire codes when you ran your diagnostic check.

Considering the EGR valve is engine-related and can cause running issues if it is clogged or not functioning properly I would say YES it is possibly the cause. Inspect the EGR tube for cracks and use vacuum to test the functionality of the valve.

__________________
-1992 Ford F-150 (winter truck)
-1998 Lincoln Mark VIII LSC (fun car)13.591@101.72mph