I have been getting a fairly substantial oil leak lately. It was significantly bad when running the car hard. It would smell like oil and also produce smoke from burning off the exhaust right by the transmission. I did the vacuum pump gasket a couple weeks ago but was still getting the oil burn off.

So, today I replaced the valve cover gasket. After my hard run test drive, it would appear the oil leak has stopped. I also took the opportunity to replace the plugs. Come to find out there were NGK plugs in it. I put in the proper Bosch dual platinum plugs. Got the gasket kit and plugs from FCPeuro. After shipping it was like $70. And EVERYTHING they sell carries a lifetime/unlimited mileage warranty. Including wear items (pads, wipers, etc.)

The job only took about an hour. Longest part was finding the torque specs for the valve cover and coil packs. Which are 9Nm and 8Nm respectively. Bosch spec for the plugs in an aluminum head is 15-22lbft. So I went to 20lbft.

So, if you're thinking of doing this job... GO FOR IT! It's not that bad. Just need to get enough slack in the wire harness to get the valve cover out.

Good going...glad that's fixed. FYI NGKs are also approved for the M271, I actually prefer them to the Bosch plugs

Should of checked the timing chain while you're in there..

There was slack in it. But I assumed the tensioner takes it up with oil pressure. Is this incorrect?

It should be tight all the time, the tensioner is spring loaded..

Incorrect, you have to put 1 cylinder in vmt and then check the slack because sometimes the camshaft rotates back when engine shuts off making the chain seem loose. You have to line up the timing marks and then see.

Well I am not getting any noise from the timing chain. I was going to do the tensioner since it's pretty easy to do. But I guess I'll hold off.