I know there are a lot of threads and discussion on the oil consumption issue, and Lexus says the oil consumption is normal.

My 2006 IS350 uses about 1 qt oil every 1500 miles even though the car and engine are in excellent condition, and all servicing and recalls are done. Car is currently at 130K miles. I don't mind adding oil as long as its not burning blue smoke.

But my concern is will the oil consumption (and causing factors--rings, valve guides etc) get worse to the point where the engine is done and engine needs to be rebuilt or replaced. If that happens then its not worth it versus the value of the car.

I see other CL members on here with hi mileage IS350s at almost 200K miles. Toyota/Lexus is known for long time durability--my 2002 Tundra had 260K miles and was still running strong.

Please advise, thanks!

 

I just posted a similar post. I'm not sure anyone can answer that question exactly. I have same car, same mileage, same problem and don't mind feeding it a quart of oil every couple months if I get another few years driving about 10k miles a year. It's almost an irrelevant question. If I say yes, the engine will blow soon what difference does it make? Either way you would of needed a engine rebuild or replacement that is more than the car is worth (or the bulk of the value of the car).

In my other post I mentioned in my research I've yet to come along anyone saying their engine blew after some time of oil consumption (i.e. faulty rings or valve guides). I may have missed it, but If you have found anything like that let me know!

I'm hoping it's like my old honda accord, where I added a quart a month and drove the car another 70k miles and for years before I sold it.

 

Could be any matter of things. Valve cover gaskets might be leaking (check that area for oil buildup), the valve stem seals may be bad (you'll usually see a puff of smoke on the first startup of the day if this is the case), could even be clogged oil return holes on the pistons (although that'd be the first time I've heard of that happening on the GR motors), could even be the piston rings themselves. But again, this is all speculation. Most likely case is the valve cover gaskets or the valve stem seals. I wouldn't even consider the piston rings themselves until the car really starts getting up there in mileage. The return holes shouldn't be clogged either unless you tend to use dino oil and let it go for long intervals.

It's just a matter of if you plan on keeping the car for a long time, then fixing the issue is probably worth it. If you'll be dumping it soon, just keep adding the oil. Whatever floats your boat, really.

 

I should of added my car did not get the recall work done for piston rings. I think the concern is given Lexus admitted there was a poor piston ring design, those outside of the extended 9-year unlimited mile warranty are out of luck.
I did check the valve cover for any build-up as well as looking for smoke at startup but all was good. Definitely no leaks. Can see a hint of blue smoke under heavy acceleration and can smell burning oil under heavy acceleration.

 

A quart every 1500 miles is quite a bit. I am surprised there isn't more blue smoke pouring out of your exhaust. This will affect your cats eventually causing damage to them. I suppose adding a quart every 1500 miles is cheaper than swapping engines. If you decide to keep the car and swap out the engine look for a a used engine out of a salvage IS350. You should be able to find a low mileage engine and have it put in for 4k. But you may be better off parting out the car at that point or selling now while it's still worth 10-12k.

You might want to go to a thicker oil like a 5w40. Also, check your PCV valve and make sure you have changed it. The less crankcase pressure you have the better at this point.

 

^X2 on the PCV valve. Less than $10 and takes 5 minutes or less to replace. Once the old one is uninstalled, shake it. If you don't hear it rattle, it was stuck=bad.

 

lol you know everything eh i replaced mine according to Mileage i don't care if it's still good or not. 10$ only why be cheap ? take you 3 mins with a 17in socket do you have an Oil Catch Can on your car Gvill350 ?