Looks like my valve seals went. Smoking on cold start and accelerating from a stop sometimes. Any suggestions?

https://youtube.com/shorts/WjveQgtpU7s?si=5g3Xk9nbsnlMSTBy

 

Does your engine oil level drop over time?

 

Yes

 

Proper diagnosis must be done.

I think you have done some but here is the list

1. Any leaks on the ground?
2. Any CEL?
3. Are you driving at higher than 55mph?
4. Compression test results?
5. Leak down test results?

What is your repair budget? How many miles on odometer and how many more you realistically expect? What is the market value as is and after repairs.
Have you played with slightly heavier weight oil/high-milage?

Salim

 

This engine is not known for bad valve seals but it's possible. Try replacing the PCV valve. Could be engine sludge causing oil to get past the rings try Valvoline Restore & Protect.

 

No check engine light it was randomly throwing a lean code until I found the split hose. I had driven quit a bit after the oil change and pcv valve replacement not knowing about the split hose. That is when I first noticed smoke. Nothing is leaking underneath. But it went from using no oil to using a lot of oil. I no longer have the tools to do compression or leak down tests. The car was free from the church so my budget is extremely low. I am having a hard time understanding how it went from using no oil to using it seems like a quart in a few hundred miles.
I am using high mileage 5w30 oil and I am currently trying some Lucas out of desperation.
Thank you.
More I think about it im probably making it worse. Its probably a sludge issue from changing the oil. I don't know how long the old oil was before I changed it. I think I might try the liquid moly stuff and change the oil again.

 

Following is just a theory: [You must verify that it is applicable in your case, by adding a catch can in the path of the pcv-air-intake].

The passage mentioned above is to capture unburnt fuel vapors from the engine block back into the air intake.
But:
If the engine over-revs [above 2.5k number I just pulled], the oil is pumped into the valve cover area faster than it can drain down ... oil, sludge, narrow drain passages etc pushing the oil level above the PCV and into the air intake. Back when RX first gen was introduced the posted speed was low and the trans gearing was such that the engine does not need to over-rev.
These days every one is going 70+ and the first gen RX is in 3Krpm + range as sustained rpm specially intra-city.
The use of heavier weight oil, [recommended for his milage] makes the return even slower.

So the best course of action is to diagnose and spend money where it will give you best return. Reaching out for "right sounding" or worst "cheapest" is not the way to go. I would over extend myself and even state that ignore this issue. It is not impacting safety and drivability at this stage.

Saliim

 

I tested the vacuum at the oil cap. I cannot feel or hear any vacuum with the engine running. I think the pcv passage has become completely blocked.

 

I have decided to pull the valve covers and clean the PCV passages. I will let you know how it goes in a few weeks. Praying its not a waste of time or money.

 

Check the pictures of inside of the valve cover,

I am not sure if the baffle can be separated ... Well I just worked the tubes to get to the seals.

Also if if the pcv passage is blocked, then you would not be loosing oil from there.

Salim

 

This doesn't sound like a good test. The front cover has a hose sucking air from the air cleaner into the cover. You could disconnect the hose at the cover and see if there is suction there.

The rear valve cover has the PCV valve with a hose connected to the air intake plenum to suck crankcase vapors out of the cover. You can disconnect the PCV to see if it is functioning and has suction. You can also see if it is very oily.

The issue described in this long thread https://www.clublexus.com/forums/rx-...lve-cover.html is about oil consumption through the PCV from the rear valve cover. Fixes include:

• Replacing the rear valve cover with a newer design
• Installing an oil catch can
• Some minimal modification of the PCV flow by addition additional hoses.
• Reversing the crankcase air flow direction

 

Couldn't get to it for a few weeks due to issues with my prosthetic leg. But handled it today and the repair was a success. No more smoke from the exhaust.

 

How did you fix it?

 

I removed the valve covers and cleaned the PCV passages. I also replaced the valve cover gaskets, tube seals, and spark plugs while I was there. I think the main issue ended up being the tube seals all three spark plug tubes on the right head had oil bur to were about completely filled with oil.