joneill1975

Last night when changing the spark plugs on my 2002 infiniti i35, i noticed a fair amount of oil on the combustion side of plugs 1,3 and 5. There was some on the outside of the plugs, but not as much as I have seen before replacing the valve cover gasket a year or two ago.

I started looking around and noticed a fair amount of oil on the firewall side of the engine. Here are some pictures.

Driver side near firewall (closest to cylinder 5)
http://flic.kr/p/dWz3RE
http://flic.kr/p/dWz3R1

Middle near firewall
http://flic.kr/p/dWz3QN

From the pictures it looks like the valve cover gasket is leaking. I know this is a common problem, but this has been replaced within the past two years, so I am a little surprised that it would be leaking again so soon. In the past when it was leaking i found alot of oil in the spark plug cylinder and not in the combustion chamber.

My question is the oil on the combustion chamber side caused by the leaking valve cover gasket or is something else going on with my engine?

03GLEmaxima

The problems with the the 02-03 valve covers are all prone to leaking into the spark plug tubes because of a design flaw. You need to get the 04 rear valve cover to fix the problem and they are really cheap. I'm getting mine from courtesynissanparts soon

Chris Gregg

iTrader: (59)

Also check www.nissanpartsasap.com and just call them. Very competitive. Great guys.

joneill1975

Would this cause oil to get into the combustion chamber?

Are the valve covers the same for the I35 and Maxima?

NmexMAX

iTrader: (22)

04 I35 is the same as the 02-03, get 04 + Maxima covers.

rebelhell

iTrader: (1)

Just bought mine from courtesyparts.com. I believe they were $30ish each. Not too bad.

D Moolah

iTrader: (1)

http://www.nissanpartsasap.com/nissa...intVehid=11341 has the rear valve cover for $28 bucks. That's awesome! I'm waiting until spring when its not single digits to replace my cover.

joneill1975

Would this cause oil to get into the combustion chamber?

03GLEmaxima

No it fixes the problem.

quick-e

I just had this completed last week. So figuring my minor miss was the rear coils. Had my mech buddy going to change the rear coils and plugs just to find the rear spark plug holes filled with oil which means the seals around the spark if holes that are not serviced/sold desperately needed to be replaced. I called the dealer to check my cost for part as I manage a body shop to my surprise they are over 200 per valve cover. WTF?? I found an aftermarket vendor Olympus to sell gaskets. Guess what they were wrong. I called another dealer tha k GOD and he said to go with the 04 not the 03 valve covers that's right the valve covers on the 04 cost me about 30 per and the 03 were over 200 per. Crazy **** man. I bought the 04 covers and had them installed. This missing idle helped but didn't fix all the way. Maybe a front coil acting up a tad bit. So to answer your question the valve cover can allow oil to leak into spark plug holes and filler up like a maxi on pump 3. And just imagine your nice coils firing away while soaked in oil. Getter dun!!!

joneill1975

My question is would a leaking valve cover gasket cause oil to get into the combustion chamber? (Not the spark plug cylinder where the ignition coil goes)

Chris Gregg

iTrader: (59)

On a properly torqued spark plug, oil will not leak past it and into the cylinder. The oil will remain in the spark plug tube and be evaporated/burned away by heat from the plug/head/engine.
Do you have reason to believe oil is getting into the cylinder(s)?

joneill1975

Yes....when I pulled the spark plug out they were oily on the combustion chamber side (where they spark....not where they connect to the coil).