Lifter Tapping?

Folks, does this sound like lifter tapping to you?

I swore it was the power steering pump going bad because it did have an issue, but replacing that didn’t clear this up. This is new noise that started with this this recent cold snap.

It varies with the speed of the engine and at about 2500-2800 rpm abruptly disappears.

Power is great, no smoke, no leaks, no nothing.

If it is cam related the frequency will be 2x the RPM. If it is crank related the frequency will be at 1x the RPM. It “sounds” 2x but hard to tell from just an audio clip because it is relative to the rpm.

1 Like

2x, or 1/2?

2x would be some new cycle I’m not currently aware of, or maybe some other assumptions I’m missing.

Yah you’re right. I’m not sure what I was thinking. It’s still a good way to separate a knock like that into crank (time for a short block) or heads in modern OHC engines.