Oil in spark plug, smoke from right exhaust L322 RR vogue v8

[MacRR]

I have a 4.4 2002, and I had it serviced a month or so ago (main dealer).
When it was picked up the car started to stutter and began to smoke from the right exhaust.
I took it back to the dealer and he said he would look at it. Anyway to cut a very long story short he hasn't fixed it and it still smokes.
I took the car to my local garage who is a friend of mine and he diagnosed the problem straight away.
He said it was a misfire from the front bank? Without messing with it I took it back to the dealer and explained the problem.
A few days later he said it was sorted. On my journey home it clearly wasn't.
I then returned it back to my friend who removed the spark plug and found oil inside. He reckons its coming from an internal leak and not valve cover? When cranking the engine there is a fine mist of oil spurting out the plug hole, he done a compression test and he said it was 125psi which he says is low.
I am getting well pi**ed of with it at the mo as I have just paid £2.5k for a new gearbox.

I hope this job isn't gonna cost me a fortune!!
I hope someone can help me!!

Thanks in Advance

[MacRR]

Update from the previous post..
Removed the oil breather etc and cleaned it through etc re fitted it. Car still has oil in the number 1 plug on the right bank.It is smoking from the right exhaust. done a compression test and it was 150, the one next to it was 150 aswell.
Any other ideas?

[Howitzer]

Do these rocker covers have a seal around the plug hole?

For oil to be spraying out of the plug hole with no plug in you would see large amounts of blue smoke when running.

Dave!

[Steve_D]

My thoughts in increasing order of £££s.

Valve stem seals worn or missing.
Leaking inlet manifold drawing oil from the valley.
Broken oil control piston ring.

At this time I think the manifold may be the culprit.

Steve

[MacRR]

We have discovered that the oil filter housing was all smashed and broken inside. The main dealer serviced the car last month and since it was serviced it hasn't run properly. We are hoping that it is one of the "vacuum"? lines which has been leaking over bank 1 front spark plug. That is where the plug keep getting oiled up, there is supposedly a pipe which sits just above it? It seems like too much of a coincidence that the car started to misfire on the way back from the dealers where it had just had an inspection 2. I am putting a new oil filter housing on there and will let you know how I get on.

Mac