2015 Lexus LX Diesel Spewing Black Smoke and Showing Engine Instability at High Mileage

Hey there, Just so happens I had similar issues with my 2012 Lexus LX. Mine was belching out more black smoke than a coal train and felt like I was driving through a swamp. The jerky acceleration and weird hissing sound sent me straight to bullseye - it was the turbo's wastegate valve. The wastegate valve is, in simplest terms, a pressure relief valve. It controls the amount of exhaust gas that goes into the turbocharger, helping to control the speed of the turbo's turbine and prevent it from over-speeding. When this packs up, all hell breaks loose in the boost system. It doesn't vent the excess pressure properly, the turbo can't spool up right and you've got yourself a shaky, underpowered ride with a tendency to stall. In my case, it did turn out to be a pretty serious issue, the wastegate valve was stuck open - which admittedly is a bit of a pain to sort. They had to pull it all apart, free the valve and clean everything up, then reset the engine management system. I'd recommend you get it checked out sooner than later. It's not something you can just 'live with'. It takes a bit of time to fix, but once sorted, my LX was back to its old self, running smoothly, no more smoke or weird noises. So, don't worry too much, it's a solvable issue, just nip it in the early. Hope this helps!

Hey! I appreciate you taking the time to share your experience. It's really quite a relief hearing that your LX managed to bounce back with some TLC. The wastegate valve sticking open sounds like a bit of a nightmare but the way you describe it, it seems to fit the weird things my LX is doing these days. This turbo stuff is a bit over my head but I'm getting the picture now. If you don't mind me asking, what price range are we looking at to sort this all out? Just to brace myself for the bill that's coming my way. And did anything else creep up after you got that problem fixed? Thanks again for the advice!

Hey! Yeah, glad to help you out. I understand how troubling it can be when your ride starts going in reverse mode. So about the bill, it did knock me for a loop a bit, won't lie. I splashed out around 860€ to send that wastegate valve defect to history town. But, hey, you gotta do it for your car's sake, don't ya? Once they cleaned up the valve and reset the engine's brain, it tidied up the boost pressure system malfunction nicely. Post the mechanic visit, the turbo's been a charm, and she's running just like her old self, no problems so far. Got the Lexus swagger back, you can say. Just ensure you take it to a dependable mechanic, one who knows their way around turbo systems. In the end, the bill was worth the peace of mind and that purr when you rev up. Sure does beat the jerkiness and the smoky cloud tail, don't it? Best of luck getting yours sorted!

Thanks. I needed that brutal honesty regarding the damage to my wallet. It does sound costly, yet your reassurance that it's worth the investment helps. After all, our cars are like our babies, aren't they? Thanks again for throwing light on what could be up with my LX. I'll set up a visit to my mechanic sooner rather than later to avoid worsening the problem, and fingers crossed for a smoother ride post-repair. Your detailed updates and great positive attitude have eased my worries a bit. Will update you on how things go. Until then, keep that Lexus swagger high, Cheers!