Three weeks ago bought a 2000 SE with 37k miles and I noticed yesterday that it had burned - over the last 1800 miles - about half a quart of oil. I didn't think it could be a leak because I had that checked out by a dealer (not who I bought it from) before I bought it.

Then today I come out of blockbuster and the car is idling and I smell something gross. "Poor sucker" I think to whomever owns a car making that smell and my wife leans out the window and says the car stinks and that it's us! Well damn.

It is us, but it's also very hard to localize. It seems to burn the best when it's idling. Rev high and I can't smell it at all. I will bring to the dealer tomorrow, but any tips on proving that the oil is burning...? What's the likely cause and will powertrain warranty certainly cover the engine burning oil?

An O2 sensor is bad and the service engine light soon is on because of it, but I trust that the dealer won't try and get me out of his hair by referring to that as a possible problem...

I doubt this has any relation but when I topped the oil off just after I bought it I put in about half a quart of mobil 1 synthetic, then topped it off again yesterday with the rest of that half quart. I was planning on a full oil change in the near future.

 

1 qt in 3000 miles is considered within spec and is nothing to worry about. Some cars do it, some dont. It shouldnt get worse. Some do it from day one and never really use more or less.

the smell is from the catalydic converter. The O2 sensor is likely making you run really rich. Once fixed, it should clear up. If its been left that way, it may need replacing and should be covered on the 60K warranty.

 

So you really think that the O2 could make the car smell like this? It smelled like it was burning oil - and that's a smell the car has never made before - in regards to running rich I can say for sure that the gas mileage has been perfect, for what it's worth. I'm definitely not challenging your opinion on the matter, merely trying to make sure I've explained the situation clearly Thx btw!

Tim I just filled the tank up. I'm getting about 18.2 miles to the gallon city/highway. I estimate I should be getting 23 or more based on my earlier numbers and the city/highway ratio I'm doing, so clearly the gas mileage has plummeted. This is the last 100 miles (though the o2 sensor went off about 1000 miles ago or maybe more!) that it did this because the previous fillup it was great, but I topped it off tonight just in case and 18.2 mpg is what I'm getting. I hope that fixing that relieves the smell. The use of oil is still worrisome though

 

Any smoke coming from around the engine or under side of the car? I bet you have a small leak and it's dripping onto the exhaust system. That's why you smell it when your stopped @ idle.

 

Doesn't look like it. I only noticed the smell very recently and it's rarely there, in fact. The car smells like it's burning a lot of fuel, as per the O2 sensor problem, but it did that one time have a nasty oil burning smell. I read somewhere that burning oil can wreck an O2 sensor, so perhaps that's what caused the problem, as opposed to a bad o2 sensor running this too rich and mucking things up?

Nissan wants $235 for labor and O2 sensor, but only $109 for the sensor itself, so I will try to find out how hard it is to replace and do it myself.

Another weird thing is: Twice now the oil has abeen about 1/4 between low and H, on the L range. I put in half a quart and that's enough to bump the oil-check level above the H. Is that normal? Seems a very small range of L to H if that's the case...

 

You should call Dave Burnett @ Smithtown Nissan (800) 251-7278. He will most likely save you a bundle on that part.

You could also try Courtesy Nissan http://www.courtesyparts.com

they are good, but I usually call Dave first. His service and price are usually unbeatable.

Hard to say.. I mean, gas contamination would cause your oil to burn more readily... You can always do a blackstone test for $18 or have a compression check done. Neither is expensive for some piece of mind.

 

Here's how:

http://forums.maxima.org/showthread....hreadid=100060

 

Thanks, guys. Nissan says that many oil leaks/burning are covered by powertrain, so I'm not going to worry about that for a while. Perhaps it isn't really going through oil and I'm confused in relation to it cranking through too much fuel. I will replace the O2 sensor and see how things go.

Is this an easy job? I will be buying haynes, but I can't imagine why Nissan wants $110 in labor to replace what I believe to be merely unscrewing an O2 sensor and plugging it back in. BTW it's Bank 1 sensor 2.

 

Replacing an O2 sensor is easy IF you have the correct tools. Trust me, go buy a O2 sensor socket at a local auto parts store. It will cost between 8-15 bucks.

Make sure you do it while the exhaust is 100% cold. Make sure to use the correct anti-seaze compound and you are golden. If you can reach your arm up and get a good seat on the sensor...cake. I did this on my Probe where there was NO space and it only took my about 15 -30 minutes.

 

Here's a thought. If the O2 sensor is bad, perhaps the ECM went into some version of "Limp Home Mode". If so, the ECM might have chagned the timing advance which could have resulted in more oil being in the cylinder at the time of detontation in turn leading to an observed increase in oil consumption?