Slight knocking on start up on cylinder number four

2000 LEXUS ES 300
230,000 MILES • 3.0L • 6 CYL • 2WD • AUTOMATIC
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2LEXUS JERRY
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Misfire on cylinder number four, fixed by replacing coil pack. Now there is a slight knocking on start up on that cylinder.
Any ideas?
Apr 28, 2018 at 8:21 PM
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PATENTED_REPAIR_PRO
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Perhaps from the coil not working on number four the gasoline washed away the motor oil on the cylinder wall causing the cylinder wall to wear and rings enough that now you have some piston slap. See if some STP will quiet it down.
Apr 29, 2018 at 7:47 AM
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2LEXUS JERRY
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It is more of a top end noise. I was thinking exhaust valve possibly?
Apr 29, 2018 at 8:50 AM
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PATENTED_REPAIR_PRO
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Exhaust valve doing what?
Apr 29, 2018 at 8:56 AM
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STRAILER
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If it was a valve problem it would be more of a tapping than a knocking. Can you please make a video of the noise with your phone and upload it here to the site in your reply?

Cheers, Ken
May 1, 2018 at 1:34 PM