Infamous timing cover oil leak and evaporated oil smoke and smells?
Thread Starter
Pit Crew
Joined: Apr 2003
Posts: 156
Likes: 4
From: International
Infamous timing cover oil leak and evaporated oil smoke and smells?
I've read through the very useful giant timing cover oil leak thread:
https://www.clublexus.com/forums/rx-...r-leak-13.html
Question: Has anyone seen oil smoke coming out of the engine bay and smelled the smell of oil evaporating over a hot surface? I don't believe the thread has many or even anybody mentioning that.
I am wondering if my oil leak is from there or somewhere else. It didn't seem possible as the hot exhaust manifold is some distance away. However, a video by the Car Care Nut says that the leaking oil will fall on the spinning drive shaft, which will whip the oil in all directions, such that it could land on the hot exhaust manifold.
My RX350 is a 2011 and thus it isn't worth removing the engine to properly fix this. I plan to try the @afpj and @RichS solutions:
https://www.clublexus.com/forums/rx-...l#post11711415
- which I understand is 1) clean the area thoroughly, 2) apply a good oil-resistant sealant like Permatex Black Ultra [importantly, waiting for it to cure 24 hrs], 3) perhaps sealing it with the spray sealant too.
https://www.clublexus.com/forums/rx-...r-leak-13.html
Question: Has anyone seen oil smoke coming out of the engine bay and smelled the smell of oil evaporating over a hot surface? I don't believe the thread has many or even anybody mentioning that.
I am wondering if my oil leak is from there or somewhere else. It didn't seem possible as the hot exhaust manifold is some distance away. However, a video by the Car Care Nut says that the leaking oil will fall on the spinning drive shaft, which will whip the oil in all directions, such that it could land on the hot exhaust manifold.
My RX350 is a 2011 and thus it isn't worth removing the engine to properly fix this. I plan to try the @afpj and @RichS solutions:
https://www.clublexus.com/forums/rx-...l#post11711415
- which I understand is 1) clean the area thoroughly, 2) apply a good oil-resistant sealant like Permatex Black Ultra [importantly, waiting for it to cure 24 hrs], 3) perhaps sealing it with the spray sealant too.
Last edited by Lexterious; Jan 9, 2026 at 12:44 PM.
Thread Starter
Pit Crew
Joined: Apr 2003
Posts: 156
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From: International
Everyone, I take that back.
From The Car Care Nut's deep dive video, I can see that where it leaks is in fact right above the half shaft to the passenger wheel (I think it's called a "half shaft").
See video at this point:
So maybe this common problem is what I have.
I'm still curious of any of you have seen the smoke and smelled the evaporated oil smell that I have.
From The Car Care Nut's deep dive video, I can see that where it leaks is in fact right above the half shaft to the passenger wheel (I think it's called a "half shaft").
See video at this point:
So maybe this common problem is what I have.
I'm still curious of any of you have seen the smoke and smelled the evaporated oil smell that I have.
Last edited by Lexterious; Jan 9, 2026 at 12:20 PM.
Pit Crew
Joined: Nov 2025
Posts: 116
Likes: 39
From: Palm Beach, FL
Honestly, I don't understand why everything is being smeared with sealant there... The timing cover is sealed with sealant. If it hasn't been removed, or if it was poorly cleaned or insufficient sealant was applied, there shouldn't be any leaks. A known problem with GR series engines is oil leakage from the oil pipe (this is visible in these photos) and, in some cases, from under the banjo bolt washer that secures this oil pipe to the engine. I personally replaced this oil pipe for a customer on a 2GR-FSE engine. Before replacing it, I thoroughly cleaned everything, and a couple of days later I checked exactly where the leak was coming from.
Besides these oil lines (and other faulty lines on the pre-facelift model), the valve cover gaskets can leak, and very rarely, the crankshaft seal.
Besides these oil lines (and other faulty lines on the pre-facelift model), the valve cover gaskets can leak, and very rarely, the crankshaft seal.
Pit Crew
Joined: Oct 2016
Posts: 171
Likes: 66
From: Texas
We have a 2015 with the leak. It is just seepage and doesn't leak enough to smell, smoke or lose enough oil between 5K interval oil changes to show up on the dipstick. The leak shows right at the lower left part of the water pump (in that area anyways as though you were looking at the water pump straight on from the left side of the engine when looking at the engine after opening the hood). I don't plan to do anything until it becomes unmanageable (likely well after we get rid of the car after 500K miles).
Last edited by lexflana; Jan 9, 2026 at 12:52 PM.
Racer
Joined: May 2012
Posts: 1,602
Likes: 280
From: CA
I just did this sealant patch ‘mod’ two days ago on wife’s 18 RX350. I noticed the leak at 40K miles, car now has 75K. I had been putting it off for years! Here is what I did:
1. Clean the leak area with paper towels,
2. Use a narrow screwdriver to remove excess FIPG material around leak area.
3. Wipe leak area again with paper towels, but this time dapped in alcohol - to remove any oil film and improve sealant adhesion..
4. Apply silicone sealant. I used what I had on hand, which was red hi-temp Permatex RTV gasket maker.
The mrs had to use the car in the am, so cure time on the RTV was about 15 hours. I think in a week’s time, I will be able to see if the patch job is holding up.
I had the same leak issue in the same area on wife’s previous car, a 07 ES350. That was more of a seepage and oil never hit the ground. I managed that leak by going to a thicker viscosity oil, 10W/30, which significantly reduced the seepage that I never tried the patch job. The RX350 has a bigger leak. I have been using 5W/20 oil but that hasn't done anything to the leak.
1. Clean the leak area with paper towels,
2. Use a narrow screwdriver to remove excess FIPG material around leak area.
3. Wipe leak area again with paper towels, but this time dapped in alcohol - to remove any oil film and improve sealant adhesion..
4. Apply silicone sealant. I used what I had on hand, which was red hi-temp Permatex RTV gasket maker.
The mrs had to use the car in the am, so cure time on the RTV was about 15 hours. I think in a week’s time, I will be able to see if the patch job is holding up.
I had the same leak issue in the same area on wife’s previous car, a 07 ES350. That was more of a seepage and oil never hit the ground. I managed that leak by going to a thicker viscosity oil, 10W/30, which significantly reduced the seepage that I never tried the patch job. The RX350 has a bigger leak. I have been using 5W/20 oil but that hasn't done anything to the leak.
Instructor
Joined: Nov 2015
Posts: 1,060
Likes: 360
From: Atlanta, Georgia
I've read through the very useful giant timing cover oil leak thread:
https://www.clublexus.com/forums/rx-...r-leak-13.html
Question: Has anyone seen oil smoke coming out of the engine bay and smelled the smell of oil evaporating over a hot surface? I don't believe the thread has many or even anybody mentioning that.
I am wondering if my oil leak is from there or somewhere else. It didn't seem possible as the hot exhaust manifold is some distance away. However, a video by the Car Care Nut says that the leaking oil will fall on the spinning drive shaft, which will whip the oil in all directions, such that it could land on the hot exhaust manifold.
My RX350 is a 2011 and thus it isn't worth removing the engine to properly fix this. I plan to try the @afpj and @RichS solutions:
https://www.clublexus.com/forums/rx-...l#post11711415
- which I understand is 1) clean the area thoroughly, 2) apply a good oil-resistant sealant like Permatex Black Ultra [importantly, waiting for it to cure 24 hrs], 3) perhaps sealing it with the spray sealant too.
https://www.clublexus.com/forums/rx-...r-leak-13.html
Question: Has anyone seen oil smoke coming out of the engine bay and smelled the smell of oil evaporating over a hot surface? I don't believe the thread has many or even anybody mentioning that.
I am wondering if my oil leak is from there or somewhere else. It didn't seem possible as the hot exhaust manifold is some distance away. However, a video by the Car Care Nut says that the leaking oil will fall on the spinning drive shaft, which will whip the oil in all directions, such that it could land on the hot exhaust manifold.
My RX350 is a 2011 and thus it isn't worth removing the engine to properly fix this. I plan to try the @afpj and @RichS solutions:
https://www.clublexus.com/forums/rx-...l#post11711415
- which I understand is 1) clean the area thoroughly, 2) apply a good oil-resistant sealant like Permatex Black Ultra [importantly, waiting for it to cure 24 hrs], 3) perhaps sealing it with the spray sealant too.
I would just clean the area really well and apply Permatex spray sealant in layers with an 1 minute wait time in between coats. It cures quickly and forms a very thick rubbery bond that gets into the small cracks to help slow the timing cover leak.
I used the Permatex spray sealant on my 2015 Rx350 with an timing cover seal leak and it work to keep it down to a minor drip over time that seeps through the spray sealant. I sprayed about seven coats the first time and at the next oil change I then cleaned the area and sprayed a few more coats in the area where the oil found a way out. Now the leak is almost sealed. I have only notice a minor seepage that barely form a drop that I can easily wipe off, however I will spray another coat in that area to hopefully finally seal it off.
The Permatex makes a clear thick rubbery layer that looks like shiny Vasoline. You can see the oil pooling under the clear rubber layer but the area is dry. My goal is to just keeping adding layers when it looks like the oil is finding a way out. So far nearly two years later the area is still dry except for a oil drop toward the bottom area.
Last edited by carguy75; Jan 9, 2026 at 05:04 PM.
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Thread Starter
Pit Crew
Joined: Apr 2003
Posts: 156
Likes: 4
From: International
Update: the problem has turned out to be a plugged PCV valve. It's been 3 days since I replaced it and the smoking is gone and the oil smell has diminished to a mere whiff (likely residual oil being burnt off).
My suspicion is that the clogged PCV valve caused pressure to build up in the crankcase, forcing oil out the timing cover and leaking down onto a hot exhaust manifold.
A fixed PCV valve = no more leak = no more smoke and no more smell.
I'll stop by in a week or 2 (car isn't driven too much) and report back if anything has changed for the worse again.
My suspicion is that the clogged PCV valve caused pressure to build up in the crankcase, forcing oil out the timing cover and leaking down onto a hot exhaust manifold.
A fixed PCV valve = no more leak = no more smoke and no more smell.
I'll stop by in a week or 2 (car isn't driven too much) and report back if anything has changed for the worse again.
Instructor
Joined: Nov 2015
Posts: 1,060
Likes: 360
From: Atlanta, Georgia
Update: the problem has turned out to be a plugged PCV valve. It's been 3 days since I replaced it and the smoking is gone and the oil smell has diminished to a mere whiff (likely residual oil being burnt off).
My suspicion is that the clogged PCV valve caused pressure to build up in the crankcase, forcing oil out the timing cover and leaking down onto a hot exhaust manifold.
A fixed PCV valve = no more leak = no more smoke and no more smell.
I'll stop by in a week or 2 (car isn't driven too much) and report back if anything has changed for the worse again.
My suspicion is that the clogged PCV valve caused pressure to build up in the crankcase, forcing oil out the timing cover and leaking down onto a hot exhaust manifold.
A fixed PCV valve = no more leak = no more smoke and no more smell.
I'll stop by in a week or 2 (car isn't driven too much) and report back if anything has changed for the worse again.
RTV does not reseal itself once it looses it adhesion and become contaminated with oil.
Pit Crew
Joined: Aug 2025
Posts: 215
Likes: 61
From: AB
Update: the problem has turned out to be a plugged PCV valve. It's been 3 days since I replaced it and the smoking is gone and the oil smell has diminished to a mere whiff (likely residual oil being burnt off). My suspicion is that the clogged PCV valve caused pressure to build up in the crankcase, forcing oil out the timing cover and leaking down onto a hot exhaust manifold. A fixed PCV valve = no more leak = no more smoke and no more smell. I'll stop by in a week or 2 (car isn't driven too much) and report back if anything has changed for the worse again.
Thread Starter
Pit Crew
Joined: Apr 2003
Posts: 156
Likes: 4
From: International
The recommendation from a dealer was to remove the engine and fix it properly, which would have cost thousands. The problem has currently abated, it seems.
The leak seemed to have come from the right side of the timing cover and so there's no easy way to get to it to apply the trick of putting some the RTV on it externally.
I will continue to monitor the situation.
Thread Starter
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Posts: 156
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From: International
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