tdandkd

My 99 RX200 has been consuming a lot of oil lately, roughly a quart per 1000 miles. Up until a couple thousand miles ago, it didn't consume any! I want to pull the valve covers and see if it is the dreaded sludge issue but am not sure how to do it. Any advice?

BTW: the RX has 159,000 miles, original transmission

Thanks for any info!

hypervish

What type of oil do you use conventional or synthetic? And, what OCI? The conventional at longer intervals has a much greater chance of sludging up. You may want to try Auto-RX.

jcjr

I am not sure you can attribute consumption alone to a sludge problem....

Lexmex

Well, the oil is going somewhere. What kind of gas mileage are you getting?

tdandkd

I'm using Castrol 5w-30. I change the oil every 3000-3500 miles, religiously. My current gas mileage is about 17.5 mpg, most of my driving is city driving to work, about 8 miles each way.

carguy07

A long shot, but maybe PCV valve?

noku

If it were to be a sludge problem smoking from your exhaust would be one of the indications (oil been burned off in your combustion chamber). You may have a leak somewhere. Try laying some newspaper under your engine and check overnight (weigh the paper down if exposed to wind).

code58

The idea is a good one but oil consumption doesn't ALWAYS show up in exhaust smoke like it once did. The CC runs hot enough that it can burn the oil off without tailpipe signs if the consumption isn't drastic, especially the newer the car. I agree with the PCV recommendation. Problem may not be there but it's always a good thing to put high on the list of "do not want to chase my tail" since it IS something that does require periodic attention.

wvuguy

My 99 rx300 with 140k miles was burning oil on highway speeds only. I was losing about 1 quart every 2000 miles. I did an auto-rx treatment and there is no more oil consumption. I also use Castrol GTX 5W-30. I change my oil every 2000 miles since I do a lot of short trips.

tdandkd

I do see some smoke in my exhaust, but it is very slight. You have to be looking for it to really notice it. I went to the advanced auto parts today and did not find anything called auto Rx, where do you find this product?

PCV is only 2 years old, or about 20,000 miles. Maybe I should replace it anyway just to rule it out, they don't cost much anyway.

tomstep2

When my RX's engine died due to the oil sludge issue, we had no indicators until it starting running rough and the CEL came on. I changed my oil every 3-4K miles.

I agree with Noku about trying to identify a leak. Look under the vehicle to see if there is oil leaking/seeping from the seals. Also look at the top of the engine at the valve cover gaskets.

The valve covers do need to be pulled to check if it is engine sludge. When mine were pulled off, it looked like thick mud in the corners.

Keep us posted!

wvuguy

Google auto-rx. You will need to order online. Before ordering I would suggest you open the valve cover to see signs of sludge or try to trace down a leak if there is any like others have suggested. Auto-rx might or might not fix your problem depending on where your oil is going. I would also suggest reading about auto rx on bob is the oil guy.
What color smoke are you seeing? It could be white steam (as long as its not too much) which is normal. Oil burning smoke is usually blue followed by an odor.