I know you are all familiar with this ticking/tapping/knocking issue in some way or another. Here is my experience thus far. I FIXED IT! READ BELOW
When It Happens:
, when put into drive from park. Instant tapping. When engine heats mildly, i.e. cold temps but not yet at operating temp, it is gone.
on and off, on warmer days, yes absolutely, on colder ones, not so much.
Looking at the rear bolt, to the left of the black plug wire clip. Driver side.
2003 Land Rover Discovery 2 Tapping/Ticking Location - Imgur
Here's What I've Done:
Added BG M.O.A.
to fresh oil change/filter worked for a little while, 1.5k miles. Tick/tap came back...
Checked All Exhaust
Manifold Bolts, Gaskets, Y-Pipe Gaskets. Mechanics Stethoscope verifies that the noise is not an exhaust leak.
Seems to Be Best/Loudest, most audible, corresponding tap when I am at the location near the rear most bolt on the engine. See Pictures.
Drained Out Some Oil and Added Marvel Oil
Installed Mechanical Oil Pressure Gauge (see below)
Preformed GUNK Engine Flush
Dropped Oil Pan/Cleaned Oil Pickup Screen
Mechanical Oil Pressure Gauge! (Pictures to Come)
Ebay Item #181069936405 (Adapter)
Ebay Item #190693921961 (Gauge)
Ebay Item #270927534952 (Stainless Steel Line)
Cold Idle: 40
Cold @2K: 44
Hot Idle: Fluctuates Between 4-6
Hot @2K: 38
Cold Idle: 46
Cold @2K: 50
Hot Idle: Fluctuates Between 6-8
Hot @2K: 42
FIXED: After having dropped the oil pan and cleaned the screen, I still had a tapping. I found a product online called AutoRx, two bottles in the crankcase and 1000 miles later, all my ticking is gone and I have seen a 4-5 psi all around increase. I can't reiterate how well this worked! Expensive, and only sold online, but well worth not having to pull the engine apart!