Mike Wait

Hi, I have a 2006 350z 6MT with about 70k miles on it and have had it for about 2 years.

About a year ago I put on a Motordyne exhaust and test pipes. Roughly ever since that I've been burning oil. About 1 quart every 250 miles!!! You can see the smoke when driving behind me. It's hard to pin point if its happening on acceleration or deceleration. I cant exactly remember if the issue started when I put the pipes on, but from what I recall it wasn't burning oil like this when I first bought the car 2 years ago...

I tried replacing the PCV and then tossed a catch can on which didn't help.

Ive talked to several mechanics about this, a lot of time they suggest putting the stock exhaust and cats back on. I'll likely give this a go. One mechanic said that since the test pipes don't have properly working O2 sensor it could be causing my mixture to be off and burn oil some how.. i didn't follow what he was saying. Another suggested my aftermarket exhaust may not have enough back pressure.

A lot of things like oil rings, valve seals, guides etc could be causing it.
Ive done a compress and leak down test, which were both fine.

Does anyone have any suggestions on where to go from here? And also any idea what caused it?
I'm going to put my stock exhaust back on this week.

dkmura

iTrader: (64)

Do a search, the '06 Z with the rev-up engine is a known oil burner. Whether your test pipes or exhaust had much effect is unknown, but your best bet is to do a leakdown and compression test. Determine whether your rings or head are the source of the problem is a good way to start the diagnosis.