Know there was a previous post on this somewhere but couldn't find it in search.

At any rate, did the plugs today on my 2k2 along with front and rear brakes. The front 3 plugs looked great. After taking the plenum off it became apparent there was a good amount of oil all over the back head's valve cover. Removing the coils revealed the presence of a lot of oil in the spark plug tubes; once we got the plugs out they had some oil fouling, especially the one in the middle, which was severely fouled. Guess that explains my crappy mileage and poor idle along with the occasional burnt-oil smell in the mornings.

I checked with my Nissan store to get my employee cost on the seals only to find out you have to replace the entire valve cover assy. (so he says) along with the valve cover gasket. Is this true or are the seals in fact replaceable? If so, what's the part # for em? Would appreciate any help. EIther which way I'm gonna replace the upper plenum gasket while I've got the upper plenum assy. off the car. It looked good enough to re-use this time but not betting on a 2nd reassembly.

P. S. Observations on the process after 60,000 miles:
- The OEM plugs (NGK Platinums) were out of gap almost .010" and the back 3 had light to moderate oil fouling due to the leaky tube seals.
- After installing the new plugs (NGK Laser Platinum R's) and getting everything put back, the test drive revealed that my rough idle problem (which I was suspecting meant I needed a 3rd MAF) went away for the most part. Also, the car pulls quite a bit stronger between 2K-4K RPMs and doesn't hesitate nearly as badly in that area right before it gets up on the cams!

 

I got the same problem.... back tubes too...

 

Same problem here. You need to replace your valve covers and gaskets. I used the 2004 maxima valve covers at a much cheaper cost (I think $26 or so each) vs. the 2002/2003 part number at $98 a piece. They were identical.

 

I'm at 41k, so not looking to do this for another 20k at least. Little worried on what I might find. Any tips on replacing those rear three plugs?

 

Are the rear three reachable without having to remove anything? 1 or 2 of them look like you might have to remove some stuff to get to them.

 

Nope, the intake manifold prevents you from removing them. You either have to remove it completely or raise it slightly.

 

So in that case you should probably just remove the manifold and replace the manifold gasket, too, right?

 

happened to me... after 38,000 miles i changed the plugs becuase i was the second owner wanting peace of mind... my mechanic found oil leaking in cyl-5 only and recommended that i replace the valve cover gasket... i took it to the dealer with my findings along with the sparkplug soaked in oil and they replaced the gasket for the rear bank within two days... im going to change my plugs again at the end of the year to make sure no more oil is leaking back there... i believe it was covered under the powertrain warranty (5yr/60kmiles if im not mistaken) but since you have 60k mi i dont know what to tell you... see if you can find a dealer that will input something else for your mileage and fix it for you...

 

I've heard that it is metal and can be reused, as long as you don't bend/break/heavily scratch it.

 

Good point on the powertrain warranty. I may have to move up my timing on doing the plugs.

 

For those of you who have this leaking spark plug tube seal problem, have you noticed any oil consumption when checking your oil level?

 

In my case the only time it consumed a couple of oz of oil was after a couple of WOT runs. Normal driving, no oil consumption. That is when I decided to change the plugs and see what was going on. My rear center plug chamber had a fair amount of oil.

Pedro

 

Anybody know the part number or have a link to the 04 valve cover.