Well, if oil PSI never drops down at idle when warmed up, then you are saying that oil PSI is the same from idle to 2000 rpm. That seems a little strange (once oil is up to temp). Perhaps you might consider to remove and inspect the oil pressure bypass and relief valves, which come out the side of the front cover. RAVE notes attached from overhaul manual.

Does this single squeak happen if fan belt is off? Maybe AC clutch, which rotates and has tight clearance, even when AC is not engaged. Maybe listen to starter with a long stick (maybe binding on release or something).

Just trying to throw out ideas that don't involve top of engine removal.

 

If you don't find it soon, send me your number, I would like to toss options around with you.

 

I compression tested the drivers side of the motor, results for just the drivers side front to back
170ish
170ish
150ish
170ish

I did take the acc. belt off... which wasn't easy bc i couldn't get the fan off...

it still made the noise.

Today while testing it i heard air bubbles in the heater core... i was thinking (hoping!) maybe it was just noise from air in the system... but the water pump is run by acc belt..? so since i've removed that and it made the noise this is unlikely...

however i added water to the system and it's seemed to have made the noise harder to excite... but it could also be the rotella getting varnish off of the internals (there was quite a bit of varnish on the bottom end.

i took videos on my phone... checking them now to see if they're worth posting

i've blown head gaskets in my 944 several times and it's never caused a problem like this noise and also i don't smell the sweet smell of coolant in the exhaust and it's not smoking really at all

 

as promised, here's a video which does a good job of conveying the noise and when it is an issue...

sorry i don't know how to embed it... if anyone is worried it's a virus or something i'll make a youtube acct so i can post it via yt

http://ghettocharged.com/Images/01262012007.mp4

you can see the engine can be reved to 4k with no squeak but when you floor it momentarily it excites the squeak

 

actually i've made a mistake my oil pressure readings were at water temp warm

i drove it for 10 miles this morning... even though the noise is harder to excite while stationary now, it's eaSIER to excite while moving.

oil pressure after 10 miles was 20-22 psi hot idle and 42-44 psi hot @ 2k

 

What I heard on the video would seem to be more of a knocking at low speed, and perhaps the squeak when revved up is a momentary belt squeak? But most people don't want to rev an engine that is already noisy...

Oil PSI seems to indicate the pump is OK. There was apost yesterday about an oil filter with low restriction that can boost pressure, may want to look at that. https://landroverforums.com/forum/di...estions-46975/

 

Those are not good numbers. Re-test the oil pump, this time start on a cold start looking at idle and 2000 RPM's and again when warm at idle and 2000 RPM's.
20-22 pounds at hot idle are not possible on a vehicle with some normal miles on it, the norm is 8 to 12 pounds of pressure.

 

at first i was using a compression tester to check oil pressure, i bought a sunpro gauge and 20$ brass fitting to get it to fit.. it's a sunpro so I doubt it's accuracy a bit

i will re-check oil pressure this afternoon but i'm certain that with the rotella T 15w40 in there it's showing around 20psi at hot idle..

looked at the oil filter post... i have a fram in there... i will replace it asap (as soon as local advance has it)

 

First, not related, but get rid of that Fram, they are pure junk for your engine. Any parts store will have a good extra large oil filter, like a Mobil 1-301 or a K&N 3001 or a Napa Gold.
Wait on doing your oil pressure test, only using a good oil pressure tester, until you let it sit over night and then start at cold start for better accuracy.
As for your compression numbers, they are off also, engines with your mileage will be lucky to pull 140's for compression.

 

Disclaimer- I purchased this truck with 199k on it from a dealer who bought it at auction and never took it off the auction lots' property because the parking pawl was broken and it was visably leaking coolant from "the head" which was actually the preheater on the intake/tb

i replaced the pawl myself, and basically followed all of DiscoMikes' advice to new owners wrt to fluids etc however it already had the STI wires, lucky me! and most recent oil job fram was all they had in at advance... i will replace it i am not sure it's a problem but i will replace it.

Right now i have a sunpro mechanical oil pressure gauge in, this is not good enough? any ideas where i can get something good? none of the auto parts stores here in 18360 pa have an oil pressure checker loaner or for purchase

for comp test i pulled the plugs, fuse 14, and squirted wd-40 in each cyl for 1/2 a sec; then cranked till pressure reading stopped rising, granted the numbers are higher than 140 but 20psi difference tells me something isn't great there