GM11

2018 LS500 F-Sport AWD. Got an engine warning saying there was an issue with the parking sensors and pre-collision. Was about to take the car to Lexus then warning goes away. Two weeks later, same thing. Three or four engine cycles, then warning goes away. Two weeks later same thing so I take a video of the warning, which I can post here if I can figure out how to do that. Last week, same thing, warning goes away after awhile.

Yesterday at Lexus regular maintenance I show them the video and they say it’s probably a computer glitch or whatever. Hours later they call back and say the tech noted the issue number indicates a faulty turbo seal that’s sticking intermittently (hence the warning coming and going).

New part is $8k and three days labor as requires removing entire engine to access. Plus tax will be $14k all up. I am now one month past the six-year engine warranty period but they will cover it under warranty, based on my description that issues arose before the end of the six-year period. Parts ordered and they will repair in approx 3 weeks time. In the meantime the car feels normal to drive like there is nothing wrong, other than the warning that pops up occasionally.

I asked whether same thing might happen to the other turbo and service advisor says there is no way of telling. They had never heard of this issue with LS500 (but I don’t think they handle many at my dealership). He said they were aware of this seal issue with another model with same engine type, one of the Toyota models (he didn’t say which one).

I’ve only done 39,000 km in this car in 6 years. Mostly a weekend driver. A lot of short cold trips (Toronto) but don’t rev the engine or drive aggressively. I faithfully take it in every six months following all of their recommended services inc. oil changes etc.

Was going to keep this car for 10 years minimum but now not sure. Wife is nervous we might now have expensive unreliable car with crazy future repair bills.

dan25man

I have not seen anyone else have issues with the LS500 turbos. I know for some very early build cars there was a valvetrain issue? And, I think, there is an open recall notice for the high pressure (HP) fuel pump for the LS460 and LS500 engines (as well as many more Lexus cars with HP fuel pumps).

You're always welcome to go to another dealer/shop and get a second opinion. It doesn't sound like the issue you described is related to what they wrote you up for... if the car was having a turbo issue, you'd have a engine warning/service, not a parking sensor issue... Cars don't glitch like the 1970-1980's. Modern Lexus/toyotas are reliable, accurate computer systems. I'd personally want to know what codes the service technician pulled from my car, then do some research on my own. It is strange that the seal? is wrong? Do they mean the waste gate? Or the actual turbo bearing seal between the oil and compressor/turbine areas? As a customer the service advisor is just relating to you what his service technician/team is telling them. It's possible the technician is being lazy and improperly diagnosed it and knows that replacing the turbo will fix the issue. And if you do go thru with the repair, I'd want something in paper that says they'll %100 cover all the costs, (because Lexus corporate) could deny their warrantee claim after they do the work.

GM11

Thanks for the advice. Agree it does not seem right. I will obtain more information before agreeing to a repair.

dan25man

Yeah, let us know what you find out. If anything it'll be a record for other members to look back on and troubleshoot as these cars age. I'm not quite in a LS500 yet, but plan to own/service/repair it myself so more data points are better. Hope, whatever the fit is, is not too expensive!!!

Lingus

If a turbo seal went bad, you be burning oil among other things. Is the oil level dropping? Also you'd have oil on the compressor side of the turbo and in all the boost piping downstream from the turbo. I just priced a turbo assembly for the LS500 and it amounts to $3200.

Whomever you're talking to is blowing smoke up your a$$.

SpudsMcD

Based on what you wrote, my best guess is that the wastegate actuator valve is sticking intermittently. That is not a $14K repair, unless it's done at the dealer, and they're replacing one entire bank of turbo components, which is probably what they're planning to do. I would have them do the repair, given that it will be free. Tell your wife not to worry, a good independent specialist shop could replace the wastegate for (I'm guessing) at most $3K. Just keep driving the car for many years, that's how you save money with these cars. Also, I've not heard of the LS having these problems, although the Tundra did have some turbo issues on launch with basically the same engine.

GM11

As far as I can tell, the car feels fine. I'm not sure about the oil level dropping; they changed the oil last week as part of servicing and they didn't mention anything about the oil level. Everything seems normal other than the warning, which cycles through these three messages:
- "Parking Support Brake Malfunction. Visit Your Dealer"
- "Secondary Collision Brake System Malfunction. Visit Your Dealer"
- "Check Engine. Visit Your Dealer"

GM11

Ok, here is what they said:

Found DTC P25B372 for turbocharger wastegate actuator "A" stuck open. Performed diagnostic and consulted with TAS. Next step of repair manual is to replace turbocharger assembly bank 1.

SpudsMcD

That's what I thought. Makes sense, and these modern turbos have an internal wastegate (no blow-off valve), so you can't replace just the wastegate by itself. I'd let the dealer proceed with the repair, and be happy that Lexus is covering it under warranty.

dan25man

Wow, interesting, glad they communicated the technical issue to you. Good to know. How even does that go bad? are they electrically driven wastegates on the LS500?

Hope the repair works and your car is good as new again!

Lingus

It is still not clear to me why the tundras had problems with their wastegate arrangement. Although their turbos are larger they share the same mode of operation. Although I be speculating, I'd wagered these turbos sustain substantial coking as a result of PCV and EGR. I'm not a big fan of these fixed nozzle turbos. There are too many limitations with them.