I worked on 2 350Z's that were losing a documented 1 qt. per 1000 miles. The plastic "tappet" (valve) covers were leaking a small amount of oil onto the exaust manifolds and it would just burn off. The amount was small enough that you could not smell it but added up over time?
I replaced the gaskets and the oil consumption was gone!
Look aalong the cylinder' head above the exaust manifolds, towards the rear corner of the heads where the plastic and the aluminum meet.

 

Farren,
For the not so technical folks, can you explain in some more detail where to look and for what are we looking for? Would I have to remove things to see that point?

Thanks!

 

Per the dip stick mine does not seem to use any oil between changes. Changed at 1200 and 4000, now at 6000 and will change to Mobil 1 synthetic at 7000 miles. Have been using dealer change with dealer provided dino for breakin purpose.

 

Farren:

As per 350ed stated, can you elaborate a little. I scannd the entire technical manual for "tappet" and nothing came up.

 

he's talking about the valve cover gaskets

 

I broke mine in by the book (well maybe one time...). Switched to synthetic at 3000 miles. It uses zero oil in 5000 mile OCI with Amsoil ASL 5W-30. I dirve it to work (8 mi./20 min.) and thrash it in the Blue Ridge mountains.

 

I drive the **** out of mine. Mobil1 syn 5w30. I know I started this post saying I was losing oil, but I really am not losing any. After recently draining, I got about 5qts out. It took a while to learn how to use this retarded a$$ dipstick, but now I can check it no problem. Levels have been good. 10,400 miles of hard driving and plenty of gtech runs

 

Just look to the farthest left or right side of the engine just above the exaust manifolds. The drivers side (B2) is easier to see!

If your one of those guys who washes their car and engine on odd days and take a shower on even days then you may never find the oil leak as you wash away the evidence! You might even seek some professional help! (for your car too!)

 

FYI as per Nissan Techline:
Let the engine sit for 20 minutes after being driven (or brought to normal operating temperature) to allow enough time for the oil to drain back into the pan. Then you can accurately check your oil level. The emphasis is on consistency! Then document exactly how much oil is added to bring the level back up to full.
Perform this inspection every 1000 miles if you think you are using oil.
This is the same inspection the Nissan dealer must perform to verify your complaint.
* Your documented results cannot be used to justify a repair by Nissan! The test must be performed by the Nissan dealer. Your results if performed and documented in a scientific manner will get you more credibility with Nissan than just pulling into the Service Department and saying "um, I'm having to add some oil to my car every so often..."

 

Thanks Farren. So I guess if there's ANY oily residue there that's a bad sign right?

Any other 350z gotchas you can share?

 

Keep in mind that if you are not having an oil consumption problem then an oily residue may be considered "normal seepage" and would not warrant a repair.
I'm just saying that in my experience, replacing the valve cover gaskets resolved the oil consumption problem and there was no need to replace the engine!

 

i had to replace a shortblock on an 02' rsx due to oil consumption. the main thing to do is get documentation started at your dealer if you believe you are burning too much oil. a qt every 1K is considered normal and anything over that i would take it to the dealer and have them take a look. they will change your oil for free, document the miles, and then you take it back in after 1k miles....you do this a couple of times and then your rep will make the recommendation. again, i will stress getting things documented because without that you are not going to get jack...

 

My car is #153 off the line. I broke in the enginge as normal. Now I have ~15k and only use it for track days. I tend to burn 1/2 quart per track weekends. It seems to depend more on how hot the temp. is. ie- I tend to burn more in the summer months on track.