Jaguar oil filter V-12

[gregma (Greg (1988 XJ-S V12 Lucas))]

We were talking about this last November, the Moose Call.

Lot of theories, including oil filters, but IMO the probable cause is the oil pressure regulator.

Groaning moose sound on cold startup

I’m trying to diagnose a sound that I’ve been having the last 6 months from the engine bay. Sounds like a moose far off in the distance. It’s a groaning/howling sound that is deep and medium to high pitched which slowly rises in pitch, then suddenly shoots down in pitch (like someone has shifted to the next gear) and then slowly rises higher in pitch , and keeps repeating this pattern for 10 seconds to 1 minute until it finally just fades away. It ONLY happens after first starting engine sto…