Chasing this Engine Tick

Dan Poelstra · March 21, 2022

https://youtube.com/shorts/bt20_L0XqUQ?feature=share

I've posted this around looking for anyone who's seen this before. No luck...

I recently picked up this truck. Had one owner most of its life with good consistent service records.

99 5.3l. Good oil pressure, no misfires codes, no codes at all for that matter. Runs perfect except for this tick.

The tick Shows at about 1500 rpm, silent at idle. Doesn't really matter if engine is cold or warm, load or no load. Always there between 1500 and about 2200 RPM... I've tried Lucas oil stabilizer and Mystery oil...no effect. Recently drove it over 300 miles in a day, still no change. Appears to be crank speed, not cam speed, I think.

I got a stethoscope and can only really hear it through the second valve cover bolt, even at idle when I can't hear it normally. Valve cover itself can't hear it, just on the one bolt. I've searched for exhaust leaks and can't find anything. Doesn't sound like lifters or even piston slap...just a different sound. I was thinking rocker arm or valve spring, but that would be cam speed...Doesn't make sense. Doesn't even sound like a rod knock...

I'm hoping someone else has see this before before before i start removi g val e covers.

CamGTP · March 21, 2022

Sounds valve train to me, like a lifter.

Piston slap sounds different than that in my opinion.

EightTrackHits · March 21, 2022

I’ve had a very similar tick recently. It was a loose spark plug. I thought it was exhaust, but I was looking around under the hood and saw one of the plugs dancing around.

Dan Poelstra · March 22, 2022

I'm afraid it's a lifter, but its so quiet at idle. I get a little lifter rattle at cold start up, for about 30 seconds ds or so...different sound to my ear...

I haven't checked spark plugs...I'll do that.