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Start the engine. No discernible missfire.
So I do the cylinder drop test to see if the coil's chooching.
Pull the coil primary connector off.
RPMs drop, but rod knock noise starts. Not click, clack like a lifter.
Clunk, clunk like a wrist pin.
Put the primary back on.... no noise. Smooth. No missfire.
Pull the primary on coil #6. RPMs drop, but no clunk, clunk.
In the old days, shorting out the plug or pulling the wire made the rod noise go away.
Turning the plug off on this guy makes the noise.
I suppose a compression miss is possible if the piston is flopping around changing the compression ration in one hole.
Piston Slap ?
Other random ideas not connected to the misfire code --- crank pulley has play on the crankshaft or torque convertor is moving on flywheel drive plate.
" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)
Last edit: 8 years 10 months ago by Andy.MacFadyen.
