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Q: Valve lash is good,check rod bearings. Engine taps under load.doesnt tap when in neutral and revving engine. Timing off 1 tooth?

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Valve lash good,rod bearings good. Engine taps when under load. Doesnt do it when in neutral and revving engine.engine has very slight misfire.Could timing be advance one tooth?

My car has 147243 miles.
My car has a manual transmission.

A: Hello. Check intake vacuum at idle to &quot...

Hello. Check intake vacuum at idle to "guess" as to the status of the timing. If below factory spec., for example if as low as 15 inches or so (vac. gauge reading), you might be off a tooth. Really, the only way to tell for sure is a visual examination of the crank and cam positions. If there is really a misfire, it should be setting an engine code that is downloadable. I would only be suspicious of timing as a cause if you recently changed the belt or the belt is overdue for replacement and the engine has been heavily loaded, loaded enough to force such a jump. In your circumstance, you should start with a comprehensive ignition and fuel system diagnosis to see what sort of issues might be causing the misfire. YourMechanic can assist you with this if you would like.

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