The oil pressure light on our 2004 G35 sedan flickered on and off a few times the other day, which had never happened before. So I checked the oil, and it was low - really low. I had to add 2 1/2 quarts to top it up.There's a minor oil leak, which I first noticed some months ago - but I don't think that's the real issue.

So I did a bit of cursory inspection and noticed that there's some white-ish smoke coming from the exhaust for about 30 seconds on cold starts - which usually indicates burning oil. It's not a big cloud, just a few white puffs. So it's unclear whether this is a real problem, or just a minor issue due to age (that might not affect drive-ability for years yet).

Beyond that, I noticed that the exhaust is only coming out one of the exit pipes. This seems odd to me, and I can't imagine a reason for it. Is this normal? What could cause this?

This is the first major problem we've had with our G35 in the 11 years we've owned it. We plan to have the car for many years to come. I'm monitoring the oil level to observe the rate of loss, which might help in troubleshooting. But beyond that, I have no idea what to look for.

Does anyone have any ideas for what might cause this constellation of symptoms? What should I look for?

 

It's pretty common for the 3.5L to experience oil burning, especially in higher mileage. The main cause is the rings, which are a known issue.

Unfortunately the main solution here is to now carry 1-2 quarts in the trunk, and frequently check the dipstick. That's a bandaid as opposed to installing a new short block.

Some guys have had luck with replacing the PCV valve, and/or installing an oil separator.

My 2006 with 150K miles burns about 2-2.5 quarts per 3500 miles. I recently changed the PCV valve and it looks like that reduced the consupmtion. Im nearing an oil change and have only had to add 1.5 quarts now, so that helped a bit.

 

White smoke on start up usually means bad valve guide seals. However once you get the Cat up to temp, it will burn off most smoke unless it's really bad. You might pull the top of your intake plenum off and look for pools of oil. If you find it, use a "catch can" on the PCV circuit.

 

Locate the leak and have that fixed. Pull your pcv valve and clean it with carb cleaner, shake it if it rattles there's never a reason to replace it! After the leak is solved and your pcv valve is no longer a possible issue check your oil level every few days until you're satisfied you don't have an OC issue! (continue checking oil level weekly)
Gary

 

About the muffler. At low RPM, the sedan only uses 1 port. The 2nd one opens up at higher sustained RPM. So it's normal operation

 

PCV vales are not expensive. So, why not just get a new one?

 

Because fixing something that isn't broken is your mechanics job b

 

They just get clogged and sticky from oil residue. With some elbow grease, you can clean up the original to the point where it's no different from buying a new one. Only real reason to replace it is physical damage.

After you clean it you can easily test it by blowing on it. You can suck air through, but if you try to blow it should lock up.

I bought a new one just because I had placed a large order for parts through Rockauto and decided to just pick up a new one.


But so far, i have noticed a reduction in oil consumption. No other changes other than PCV. Don't get me wrong though...i still use oil.

 

Home Depot oil catch can plz?

 

Actually i'm in the process of researching how to do this....

 

Search there's a sticky with pic, any lame duck could install a Home Depot catch can...Gary

 

Are you a big HB fan?

 

You mean this one?

https://g35driver.com/forums/engine-...catch-can.html


Looks like home depot trip this weekend.

 

No I'm a fan of not allowing oil residue in my plenum, this mini catch can will do the job!
The HomeDepot catch can will do the job! If you'd like to step up to one that looks better for more options...Gary

 

Hanna Barbara cartoons is what I meant. Is the HD catch can actually good for engines that don't yet burn oil? HP increases are always nice

When I installed my P spacer I noticed a lot of dirt...? Oil in intake is that why?