I would not use any of those products in your LS460 personally.

 

William has an RX with over 300K miles, that's burning a lot of oil, but not leaking. What would you suggest? Good used engine swaps are another approach, if one is willing to invest $$$ in a high mileage vehicle such as this. Personally, I'd be in the market for a low mileage copy if I was stuck on this model.

 

I was referencing the OP. At that age you really have nothing to lose, and an RX concerns me less than the LS460.

 

Is your check engine light on for P430/P420? I had that code for a while and needed to address it as the car needed to pass PA emissions. I added cheaters on the 02 sensors. Passed emissions and as hard as it may seem to believe my oil consumption completed disappeared. Over the last year I drove the car a ton and never even changed the oil just the filter. I never changed the oil because I was adding oil every other week and it was always golden. Since adding the cat cheaters my oil is dark like is should be. I just changed the oil over the weekend and pulled out 8 quarts of dirty oil and replaced with Mobil 1. I've put over a million miles on Lexus cars and trucks and do all of my own work. No one can convince me that the oil consumption being stopped was a coincidence.

 

"I added cheaters on the 02 sensors". Hmmm....You might be onto something here. Interesting.

 

Did you have a strong sulfur smell too or just the inefficiency code?

 

just the code
Oil consumption nearly disappeared after adding the cheaters

 

Fack.

So I've been burning oil at a steady rate of 1 L / ~1200km.

Then I started filling up with Pennzoil Platinum 5w30 from Natural Gas and sometime after that I've noticed that my cats started smelling real strong after hard accels, then my cat innefficiency code came on. But at the same time now I'm burning 1 L / ~400 km. I checked my PCV and it rattles but I ordered a new one.

I am running a 2006 GS300 though, not an LS. I believe my cats are smelling and fouling up because of the oil I was burning. Then the sulfur smell because it could not react with all the fuel.

So I will replace PCV valve this week. Monitor consumption.
Do a piston soak with Marvel Mystery Oil and switch to a different synthetic 5w30 oil. Monitor Consumption.
if oil consumption improves, I will try running the defoulers on the O2 sensors see if that has any affect.

If it continues to consume, may be time for a different vehicle.

 

What is a cheater and how does it work? What is the theory as to how they can affect oil consumption?

I'm a believer in using Marvel Mystery Oil or Seafoam oil treatment to free up sticky rings, which can cause excess oil consumption. On the other hand, I'm not a believer that synthetic oils, regardless of source (like natural gas), has much, if any, affect on oil consumption. Of course the biggest cause of excess oil consumption is owners not sticking to the recommended oil change schedule.

Using a heavier weight oil, or using a "stop burn" product can help with oil consumption. Too, both burning excess oil, or gas, can destroy a cat, so generally, either problem should be addressed ASAP as OEM cats can run $1,500!

 

Try about 5-10min at 120+ a few times to get the rings moving again. Or just some sustained high RPM is what I'm getting at.......usually engines burn oil when people don't break hem in hard when new. The rings never seat properly........

You can attempt cleaners, seafoam works but you should apply it though the spark plugs holes. Remove all 8 then pour 1-5 Oz per cylinder and leave it over night, then slowly hand rotate the engine and vacuum each cylinder dry. It will smoke insanely badly when you start it and will throw a cat code and miss a little, that's normal. I've had lots of success with BMW engines using that method but never had to do it on a Lexus. For my cars I just ran them for a while over 100 to make sure everything was moving and it fixed the RX consuming oil when we first got it.

 

A cheater is a little spacer that goes between your O2 sensor and the exhaust - it essentially places your O2 sensor out a little further away - and it allows the car to pass catalyst efficiency codes. It’s illegal and it also works. It’s also a cheap cheap “repair”.

And it WILL DO ABSOLUTELY ZERO FOR OIL CONSUMPTION PROBLEMS.

It has ZERO to do with your oil, or what’s causing oil consumption. It’s not physically even in the same area. To suggest (or believe) that it stops or lowers oil consumption is as fictional as believing that the Easter Bunny drops magical turds down your dipstick tube at night, and stops oil consumption. In fact, having the Easter Bunny drop magical turds into your engine at night would be more plausible than having an O2 sensor spacer stop oil consumption.

As for oil consumption on a higher mileage LS460...I would expect that the oil rings are carboned up and will not expand back out their lands. Low tension rings do this a little too often nowadays on too many engines across too many manufacturers. It was all part of CAFE regulations and there’s not much you can do about it. It’s not necessarily “worn rings” it’s dirty carboned rings that can’t expand out and do what they were designed to do...and it’s almost impossible to free them up. But it’s probably worth a try. Piston soaks, various products, shorter intervals. In the end it may improve more upon just driving and all that engine heat/movement/cycles/temperature changes having an effect on those rings. Or nothing will happen. But people have been known to drive oil burners for 100,000’s of thousands of miles and just add oil. But it takes a little effort and extra $$.

 

here they are https://shop.advanceautoparts.com/p/...E&gclsrc=aw.ds

Not sure if O2 sensor in LS460 is 14 or 18mm

 

Exactly, hence why I mentioned to perhaps just really stand on the throttle for a while.....it does actually work for some cars if the rings are not totally seized up. Naturally better and more often oil changes should help prevent the seizure from occurring in the first place. You aren't totally screwed if it does happen but it will take some effort to try and get them moving again

 

This echos my thoughts too, but I was asking the question to the poster BT3100, who claimed cheaters reduced his excess oil consumption. I'm interested to know his theory, such as....was tricking the ECU with a false reading changing fuel trims, and could this affect his oil consumption? Or, what?

 

My LS with 135,000 miles sips oil, occasionally. Can go a few months with no oil consumption, then some with increased consumption- i think it is worse in winter, better in summer. Never looked into it much as it's maybe a quart every 3,000-5,000 miles, and really only in wintertime. Mix of city traffic and highway, prolonged idling at times. Just picked up a used BMW 550 with half the mileage and pretty sure it will go through gallons of oil in the same span if I still have it at 135,000 miles.