ZD30 2006 auto oil leakage from cover plate on top of rocker cover

Hi guys,

The car was leaking some oil, after power washing the engine I managed to somewhat locate the fresh oil leak trail. It appears to have come from underneath the black cover plate that is mounted on top of the rocker cover. Now I assume this is possibly an anti vibration plate? Is there anyone that knows what that black plate is?

Took the intercooler off and some of the piping as well as the throttle body that connects to the intake. Managed to get the cover plate off and give it a good clean. The foam was absolutely saturated with oil, I think from small leakage from blow by. As there is no oil system going through the foam I assume the car is still leaking somewhere, I just can't figure out from where.

As the intake was open, minor carbon build up in the intake, not something to write about all good. After assembling everything the oil does not drip from the foam anymore, until the next time it will be saturated.

After driving around for a couple of days it's noticeable that it is a bit oily but nothing obvious. I only ripped some parts apart, inspected them gave them a clean and reassembled. I did not repair anything. Has anyone encountered this before? And if so, possible solutions?

For reference I've added a picture so you guys know what the hell I'm talking about :) You can see the black cover plate on top of the rocker cover.

FYI in my younger years I was an apprentice car mechanic but never finished education. 4 years of work in road trucks, cars and boats. So I have some knowledge but not enough. Very keen to do DIY project, just lack confidence and knowledge.

Cheers and hope to get some opinions on this.

If I'm not clear enough please ask me to clarify, it's clear to me but maybe not to you guys :D

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That plate a is supposed to be a heat shield to assist in stopping radiant heat getting to the intercooler. Why it has oil soaked it if? Your intercooler is leaking boost pressure and oil vapours that enter the air intake from the crank case breather to before the turbo are also leaking out. Two things you need to do here . 1. Buy a new welded intercooler, not one with crimped end tanks as they leak from factory. 2. Instal an oil catch can. This is a filtration system that goes inline from the tube that runs from the rocker cover to the intake pipe (after the air box and before the turbo) this will remove the oil vapours.
Oh and 3. Getting an EGR blanking plate and block that off too. This will stop dirty exhaust gases going back into the engine.


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Hi Mudski,

Thanks for the reply. My mechanic told me to get a oil catch can and explained how it catches all the oil vapor before it gets re-circulated in the system. This is something on the to do list.

As far as the intercooler, it is definitely leaking on multiple spots, you can see the black build up where the pressure has gone through the seals. Thanks for pointing that out! Do you have any recommendations for a good intercooler?

I've heard about the EGR blanking plate, seems to be mixed opinions about that one. Some say to leave it, some say do it. Not quiet sure what I'll be doing with that.

Cheers bro!

Catch can, the Provent 200 is the best. Intercooler, Petty much any out there will be better than what you have. Its only a 3L, so no need to go crazy $$$ wise on this in my opinion unless your looking for bigger HP along with other mods. No brainer on the EGR plate. Do it!