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2000 Ford F-150 Question: my 2000 f-150 5.4 v8 has a very rough idle



, 5.4L V8, Bakersfield, CA, February 08, 2011, 13:52

idle is always rough, this problem started as a result of
replacing the timing chains. Can this problem be a result
of improper timing between the two cams. Could this be the result of a vacum leak.Truck has approx. 220k miles

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  • Answer #1

    February 08, 2011, 14:00

    why did you have the chains replaced?? did one break??

    I would start with a compression test first to check for valve damage.

    Yes. a vaccuum leak will give you a rough idle. the chains out of time will give a multitude of issues.


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    , February 10, 2011, 18:46

    The chains did not break, they were worn and making noise, there was no valve
    damage. If the EGR is mounted directly behind the throttle body, I removed the
    vac line that attaches to a diaphragm actuator on this part, put my finger on the
    connector and felt no suction at all. Removing the vac line did not effect the idle.

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