After doing some extensive maintenance on my 2002, which included running a quart of ATF with an oil change for 200 miles to help clean out the internals a bit. I found that the RX would create a big blue smoke cloud from the tailpipe whenever I started it in the morning after driving and then sitting overnight.

I thought this was the valve stem seals going bad which was possible at 140K miles but that it happened so quickly made me suspicious. I wondered if the quart of ATF for 200 miles could have caused a problem but I never had an issue with doing this on other engines. One morning, I disconnected the PCV valve and plugged the vacuum hose to see what would happen on start-up -- almost no blue cloud this time. Interesting.

I replaced the PCV as part of the maintenance with a new dealer one so I assumed it was fine but when I removed and shuck it, it sounded like it was jammed inside somehow. I quickly replaced it with one from my local Napa. After driving, parking overnight, and starting the next morning. the blue smoke was completely gone. Problem solved.

The don't think I got a bad PCV from the dealer. Rather the ATF clean out probably freed up some crud in the valve cover baffle area by the PCV opening that got drawn into the PCV and jamming it in the open position at all times causing it draw excess oil back to the intake.

Nice to have a cheap fix to what felt like an expensive problem.

 

I have an unproven theory about engine oil making its way into the air intake due to low flow down rate of oil compared to volume being pumped up causing the oil tp make its way through the pcv. This is based on high speed [high rpm] driving. Normally only unburned fuel vapors are supposed to pass through the pcv back into the intake.

My unproven/unsubstantiated would kick in if the rpms are held over 3k. [just another guess].

Try a catch can in the piping to really capture engine oil.

Salim

 

I haven't done any freeway driving since I put in the new PCV., just highway driving like 45-50mph. I will be doing some freeway driving tonight so more like 60-70 mph. That should get the rpms around 3K or over.for a period of time. Will be interesting to see what happens when I start it tomorrow morning.. .