M21... using 15w40 liqui-moly... troubleshooting jumpy temp gooahj for past 2 days... doing basically nothing but idling and occasional 1/2 mile trip around the block...
Never did solve jumpy temp gooahj, but now unusual engine sounds and more blowby than I recall. Listen between 15-17 seconds in.
https://www.youtube.com/watch?v=5vhJixen8rc
Took valve cover off, nothing loose or bouncing around, no carbon buildup or exhaust leaks, definitely tick/knock.
Have not tried yet:
- looking for bolts sticking out (as if hitting pulley)
- removing tube from vacuum pump
- removing belts
How could an engine sound so perfect just 2 days ago?
tick/knock not there 2 days ago
Re: tick/knock not there 2 days ago
Rotella T to the rescue! Sound is back to normal.