Engine maintenance suggestions?

[jjonez]

I'm planning on changing the spark plugs and leaky valve cover gaskets soon on my 2002 VQ35, and was wondering if there was anything else worth addressing while I had everything apart. From what I understand the intake manifold has to come off to get at the valve covers.

 

I do have the oil consumption issue so I was hoping there could be something I could do to mediate it a bit. I've read there was an updated valve cover that can be purchased but that it most likely won't help, and I don't know what the correct part number would be anyways. I've also heard the PCV valve can be a culprit, and that installing an oil catch can somewhere helps keep the intake manifold from getting dirty, but I don't really understand how all of that works.

 

 

Details aside I would just like to know if there's anything else I should do when dealing with the plugs/valve cover gaskets, and more specifically things relating to oil consumption. (BTW I have a 5 speed so no power valve screws to worry about).

 

 

 

Last thing, I was under the impression that iridium plugs are better than platinum, but NGK iridiums are ~$2.50 cheaper per plug so now I'm not so sure. Should I just go with those?

 

Thanks for the help!

[Saturn]

If you have a later VQ like mine you'll have plastic valve covers (earlier ones had metal covers) in which case I recommend you replace the covers and gaskets because the covers will have warped and the spark plug tube seals, which may be the actual cause of the leak, can't easily be removed from the covers without cracking them. I paid 400$ for the set because I had to rush them from the dealer but they're available online for less. I also replaced the paper intake gaskets while I was in there. I use iridium plugs, 40K miles later no problems. I do think that it's worth noting that with older trucks one oil leak is often replaced with another when fixed. My rear main seal went bad 5K after the valve covers, and my oil pan 10K after fixing that. At this point I just park over a metal tray and check the oil regularly.

 

Other threads related to this: http://www.nissanpathfinders.net/forum/topic/43099-thinking-about-replacing-your-vq-valve-cover-gaskets-read-this-first/?hl=%2Bvalve+%2Bcover+%2Bgasket

 

http://www.nissanpathfinders.net/forum/topic/42013-valve-cover-gasket-replace-help-35l-2001/?hl=%2Bvalve+%2Bcover+%2Bgasket

 

http://www.nissanpathfinders.net/forum/topic/41476-2004-pathfinder-le-valve-cover-question/?hl=%2Bvalve+%2Bcover+%2Bgasket

 

http://www.nissanpathfinders.net/forum/topic/39946-oil-leak-woes/?hl=%2Bvalve+%2Bcover+%2Bgasket

 

[jjonez]

Hey thanks for the links, lots of good info there. I do have the plastic valve covers and I can't find replacements for less than ~$170 each before shipping. At this point they're just seeping along the edges a bit, no drips so I guess those will be left alone for now.

 

I was of the mindset of taking some steps to reduce oil consumption while addressing a simple maintenance item at the same time, but of course nothing is ever straightforward. I'm pretty sure the spark plugs are 40K miles overdue though so I will definitely be changing those and praying that the plug tube seals are still good.

[jjonez]

Replaced the spark plugs yesterday, an easier process than I was expecting. The old plugs were certainly original, and the gap for all of them had widened to 0.08, 0.09 at the worst, crazy. The tube seals seemed to be okay from what I could see, however I shined a light in the cylinders and from the limited amount that I could see the piston heads looked nasty! The carbon build-up even looked slightly shiny, could this be a byproduct of the oil consumption? In any case the engine did and continues to run excellent, startups are maybe just a little easier and more confident with the new plugs.