romanlutsk

I finally got my dream car (2008 Lexus LS600hL with rear executive seat package). It's got around 180K miles and starting to burn coolant (white smoke from the exaust pipe and coolant expansion tank under pressure). It's not terribly bad yet, but the white smoke is clearly visible when it's warming up.

Would it be safe to use Bars stop leak headgasket sealer with carbon fiber? Should I try Blue Devil first (or instead)? Anything to pay particular attention to?

Just wondering if anyone has already tried any of those and what the results were. Thank you!

Cape600L

You need to take a hard pause. Are you sure it is "white smoke" on warm up? Not just steam from a warm exhaust and cold ambient air? Second, what you describe is a blown head gasket if it truly is white smoke, that is coolant in combustion chamber and blowing back into your cooling system. If you can't afford to diagnose and fix this car correctly immediately and just want to use some voodoo (never works!) leak stop, you need to get rid of this car. You have purchased a very complicated and potentially expensive to repair auto. It will eat you alive. Especially at that mileage and age. If funds are no problem, go for it, but if you are looking for low maintenance basics, you chose wrong.

Anfanger

I would check if you have any valley plate leaks before ruining your engine by adding fluids that usually make no difference apart from clogging coolant passages.

Striker223

Do not use that, ever, for any reason in that engine. You will absolutely ruin it, it is far too complex for that "solution" to work. Are you absolutely certain you have a coolant burn issue? Have you tested the coolant for combustion contamination?

romanlutsk

Thank you all for the answers. Here are follow-ups:

> Are you sure it is "white smoke" on warm up? Not just steam from a warm exhaust and cold ambient air?

Pretty sure. I just had it idle for about half an hour in inspection/maintenance mode (Techstream -> hybrid control -> inspection mode) and the white smoke continues to come out of the tailpipes. It's about 65 F and very sunny outside, so I don't think it's condensate in the ambient air. Besides, I could see tiny bubbles in the expansion tank/coolant reservoir.


> If you can't afford to diagnose and fix this car correctly immediately and just want to use some voodoo (never works!) leak stop, you need to get rid of this car.

Yes, I can run the combustion leak test to be 100% sure, but all signs point to a blown head gasket so far. It doesn't look like it's using a lot of coolant yet, so hopefully it's not a lost case yet.


> You have purchased a very complicated and potentially expensive to repair auto. It will eat you alive. Especially at that mileage and age. If funds are no problem, go for it, but if you are looking for low maintenance basics, you chose wrong

I know, I've been researching and looking for a car like this for over 4 years, so I know all the pitfalls. The main motivation was to own the holly grail, the halo car of the automotive world (at least as of 14 years ago). I have other cars that provide reliable and cheap transportation (2006 Corolla, 2008 Prius).

> I would check if you have any valley plate leaks

Good point. I suppose the combustion leak test should be able to rule it out?


> before ruining your engine by adding fluids that usually make no difference apart from clogging coolant passages.

Actuallly, I had great results with Bar's stop leak (with carbon reinforcement) on a 2005 Prius that was burning about half a quart of coolant every 100 miles. It stopped the leak completely, but also clogged the heat exchanger :-)


> Do not use that, ever, for any reason in that engine. You will absolutely ruin it, it is far too complex for that "solution" to work.

What's the worst that can happen? Clog the EGR and/or heat exchanger? I've heard Blue Devil is less likely to clog anything, so maybe I'll try that first.


> Are you absolutely certain you have a coolant burn issue? Have you tested the coolant for combustion contamination?

I will run the combustion leak test in a few days. Anything else I should try? Thanks again!

Striker223

You will ruin the plastic coolant directors in the heads and numerous other issues. The 2GR-FSE is one of the most complex engines in existence

Nospinzone

I am with the other guys, I would not put any leak stop product in the coolant. Not in this car anyway.

romanlutsk

Got it. Actually, the engine is 2UR-FSE. The GS450h has 2GR-FSE.

I guess my only other option would be an engine swap?

Striker223

Sorry I always screw that up since they both have R in the string. The RX has the 2GR-FXE btw not FSE

Yeah you need to swap it out or fix the headgasket, that can be a challenge since you will need to check the head and block for flatness and you must use a factory gasket and bolts. When you do that replace the timing chains and tensioners as well to avoid an issue with them later.

romanlutsk

I finally run 3 combustion leak tests and to my amazement it showed that there are no exhaust gasses in the coolant. There are no more tiny bubbles in the expansion tank as well. (I let it idle for around 30 min to make sure the thermostat has opened). According to the maintenance records from a Lexus dealer, the coolant was replaced last year/15K miles ago. Is it possible there were still some air bubles left over if the bleading wasn't done right?

However, there is still some white smoke coming out of the exhaust. I've heard that some steam can form in the catalytic converter as a part of its normal operation?

I guess I'll test-drive the car for a few hours and see if the coolant level goes down.

Anything else I can to do check? I've tried running a radiator presure test, but couldn't find a fitting adapter.

Anfanger

Yes, white smoke on cold start is normal. However, it should go away once the engine reaches the operational temperature. If the car set for a while, it might take longer for white smoke to go away. If you have a fiber cable camera, you can check the cylinders after removing spark plugs. The cylinder with coolant leak is going to be cleaner than other cylinders.

Striker223

You do have a hybrid and if you park outside the water that condenses might not be cooked off fully. The engine takes a long time to come to temp anyway and may not even be fully heated up.

Try taking it out onto the interstate and running it at 100mph for 10 min to make sure the engine is running the whole time and then idle it and see if the problem is gone.

TominPT

What are the weather conditions when you have white smoke? Cold? High humidity? Does it have white smoke when the engine is fully warmed up and on a warm day with low humidity? You might be seeing steam from condensation in the exhaust and not the effects of burning coolant, as Striker223 suggests.

I doubt very much you would still have residual air in the system from a coolant change 1 year and 15,000 miles ago.

Tdes395

in this video the leak was actually in the exhaust not the engine

swfla

iTrader: (1)

How long have you had the car? Did the symptoms just show up? Did you pay for a prepurchase inspection? Any sign of coolant in the oil? Is your coolant level dropping? A head gasket leak doesn't go away after engine is warm. The white smoke does, right? While you've done a good job of checking coolant for exhaust gasses. Taking it to a shop that knows Lexus cars to be checked over is better than adding leak stop that may not be needed. Hoping foe the best. Let us know the results.