So my car has been burning oil for the past 30k miles, i put in 1.5qts every 2 weeks. Had a compression leakdown test done yesterday and compression was 150 across all 6 cylinders. There is no visible oil leak. Car has a slightly rough idle, was worse before the spark plugs were changed. Car blows out light gray smoke during city driving. Im wondering what else could be causing the OC and smoking? Valve covers/gasket was replaced by Infiniti about 25k miles ago, did not help the OC problem.

Mods are: ztube/popcharger, 5/16 spacer, aam hfc, FI cat back exhaust, Osirus Tune.

 

If the compression is good, maybe valve guides???

What did your $tealership say about the oil consumption?

I'm sure you looked but there are about million different threads with about a billion theories as to what causes oil consumption. I haven't been able to put together any consensus.

Mine's a 06 with 6 speed, 76,000 miles, and so far, fingers crosses, no OC.

 

it could be the valve guides i guess, hard to tell without tearing the motor apart and looking.
Stealership denied long block due to intake and exhaust .

 

That sucks about getting the long block denied.

I'd pull the motor, take the heads to a good local head shop and have them take a look at them. If they're fine, that means the bottom end is shot, I'd get a stage 1 short block from Import Parts Pro for $2600,

http://www.importpartspro.com/st1blon.html

Seems like a pretty good deal

 

i have a jwt intake and a 350z midpipe and also have this oil problem, will i get denied if i take it to the dealership or something.

 

go back to stock before you go to dealership

 

i think jwt pop chargers make the engine use more oil for some reason, i just put my stock box back on and an amsoil filter on and it stoped using oil. i could be wrong tho.

 

Many will argue but free flowing exhaust and free flowing intake will cause oil extraction from exhaust valves during stroke. The valve guide seals are part blame along with piston rings that let oil seep. The exhaust or intake valves end up letting oil seep through and works its way down stream into the exhaust. I am not sure where I read the scientific info on my350z. Even with stock you will see this issue due to different revision piston rings which is the root cause but mods like free flowing intake/exhaust speed up this process along with hard driving and age. Oh don't forget the common valve cover leaks which is also where you see oil disappearing to.