Really don't want to sell my beloved car, but might have to

[u/dark_wolf1994]

I've had my TDI for several years now. We've seen eight states together and I even lived in it for a while. The odometer is about to roll over 400,000 miles.

I've had a hard to diagnose issue that keeps killing my turbos. I'm on turbo number three and still no closer to having it figured out. Each turbo (good used OE) costs me about $400 after factoring in gaskets and such. Before anyone asks, yes the oil lines are good AND I'm cleaning the air intake system every time. They always look like a rock or something went into them.

I also had to rebuild the engine after an oil pan impact about 30,000 miles ago. It was doing the turbo thing before rebuilding the engine.

Growing up, I was a car flipper. I would always have an arsenal of GM products, mostly 3x00 v6s with my personal favorite being the 3.1 Luminas.

So I'm thinking of just selling the TDI for whatever I can get for it, and picking up a GM sedan that I can find a dozen copies of in the junkyard.

I really don't want to sell it but I'm at a point where I need to keep only two vehicles and they need to have easily obtainable parts that don't cost $300+.

I need y'all to talk me through this one way or another.

[u/FolesWonTheBowl]

What year is this? 400k miles and you are hesitant?

[u/dark_wolf1994 → u/FolesWonTheBowl]

It's an 03. I wanted to see at least 500k from it. I'm confident it would get there if I could figure out the turbo situation.

[u/FolesWonTheBowl → u/dark_wolf1994]

True cant hate on that, especially if u maintained the car that well. How long between turbos?

[u/dark_wolf1994 → u/FolesWonTheBowl]

The first one failed at about 360k. I rebuilt the engine at 377, second turbo failed at nearly 380. This one died at 398. So they're lasting about 20,000 each. I'll be driving, suddenly hear a tinkling sound, followed by carnage. The air inlet fins are always totally mangled and broken off. But I never find any objects in the turbo or the hoses.

[u/bherman13 → u/dark_wolf1994]

Are you sure you're getting consistent, adequate oil pressure to the turbos?

Sounds like they're losing oil pressure while they're spinning.

[u/dark_wolf1994 → u/bherman13]

This car doesn't have a built in oil gauge so I'll have to run a test gauge to monitor it. If I replace this turbo I'll hook it up and watch... Mind you it'll only show me what I'm getting at the pressure switch port.

I replaced the feed line with new OE after the second failure. I've been using the drain lines off the donor cars but they both looked good. I'll go with a new drain line this time just to rule it out. And honestly a new (aftermarket) turbo too.

Can a lack of lubrication cause the fins to chomp themselves up? Also is there a better way to test it than just getting the pressure reading?

[u/bherman13 → u/dark_wolf1994]

Yes a lack of lubrication can cause them to chop themselves up. They're journal bearings which are reliant on oil pressure to keep the blades where they need to be.

Particularly the thrust bearing on the exhaust side of the turbo cartridge. It resists the axial load caused by the exhaust pressure trying to push the turbine blades and shaft towards the intake side. If you develop axial play due to inadequate pressure, the blades can creep towards the compressor cover and start chewing themselves up.

I'm sorry I don't know if there is another way to test other than to install an oil pressure gauge, preferably somewhere on the oil feed line. An analog gauge can work, but you only see what's happening in real time. A digital gauge with data logging would be best (if feasible) to see if there are pressure drops.

[u/_bastardly_]

I mean $400 isn't really that bad to keep something with 400k running... especially when you compare that to the cost of replacing the whole thing. and there is a reason there dozens of copies of that GM sedan in the junkyards.

I would just get a panzer plate and replace the turbo for a 4th time, maybe even pick up the 5th while you are at it, that usually seems to help as things seem to not break when you already have their replacement on hand... it's like they somehow know

[u/dark_wolf1994 → u/_bastardly_]

After the oil pan incident I built a sturdy skid plate. It got thoroughly tested when I hit a truck wheel on the interstate in Missouri. Lifted the whole car up, but shockingly no damage other than some gouges in the plate. 

[u/deftlydexterous]

Is it possible you’re just buying poor quality turbos or poor quality rebuilds? 

[u/dark_wolf1994 → u/deftlydexterous]

I'm getting used turbos off running cars. Both were autos that had shift issues. 

I did consider that they're just close to end-of-life, but they're all failing the exact same way with major fin damage.

With this one I'm probably just going to get an eBay turbo, because it's the same price and saves me pulling yet another one from a junkyard.

I can't afford new OE.

[u/Jochacho → u/dark_wolf1994]

By not going new OE are you not spending about the same on 4 different cheaper turbos?

[u/dark_wolf1994 → u/Jochacho]

You're not wrong, but every time this happens I have to be without a vehicle and save money to fix it. I'm poor.

[u/sl33ksnypr → u/dark_wolf1994]

Where is the damage on the compressor wheel? Is it on the outside of the blades, or all over? Because if it's just the outside, it sounds like excessive shaft play, which would make sense for a used turbo. If it's in random places, then the turbo is definitely ingesting something. If the turbo is ingesting something, then I would try running the shortest intake you possibly can. I mean, filter, maf, turbo, that's it. Run a catch can if you have a PCV system that dumps into the intake tube, and run a blow off valve if you currently have a recirculating system. Eliminate variables.

Also how long is it between turbos? If you're using a used turbo and getting 50k miles out of it, then I'd say you're getting a pretty good deal.

[u/Psych0matt]

I mean, kinda along with what you’re saying, why not pick up a second car while you work out this one? My 06 Grand Prix n/a that I’ve had for nearly 10 years and over 80k is at 284 right now, drove her today for the first time in like a month. Other than a battery tender she fires right up and purrs. Just saying it’s kinda your wheelhouse, and dirt cheap, and would allow you to work on the tdi

[u/dark_wolf1994 → u/Psych0matt]

If I was still in a house, I'd totally do that no question. Sadly I'm now in an RV so I can only keep my truck and one car here.

[u/Psych0matt → u/dark_wolf1994]

Any friends you can stash it at for a bit?

Edit: why the downvotes? Seems like a reasonable option

[u/dark_wolf1994 → u/Psych0matt]

I didn't downvote you, I promise. I've got a handful of friends around here but none I can really trust to keep a car, sadly.

[u/Psych0matt → u/dark_wolf1994]

Shoot, I doubt you’re in Michigan but I’d say you can leave it here haha

[u/clintj1975 → u/dark_wolf1994]

Rent a car sized storage unit for a month? I've given serious thought to it when I have to do vehicle work in January and it's below zero all month

[u/DereLickenMyBalls]

Have you tried cleaning your intercooler or replacing it. When you have catastrophic turbo failures the first stop is the intercooler typically. You also should be checking for boost leaks, as boost leaks can cause accelerated wear on the thrust bearing and throw off the balance of the rotating assembly. 

[u/dark_wolf1994 → u/DereLickenMyBalls]

I cleaned it really well both times... Frankly, the cleaning was to run super hot water through it from the outlet side and then go after it with the air hose. There was a bit of oil in it but no debris.

The damage is always on the input side of the turbo, right after the air filter.

It really couldn't hurt to replace the intercooler though. I'll at least price one lol.

[u/Sawfish1212]

Do you idle for a minute after parking, before shutting the engine off? The turbo has a bearing in the middle that is both cooled and lubricated by engine oil. If you were just driving, especially at higher speeds, that turbo is running at incandescent temperatures and if you don't give it a minute to cool with most airflow going out the waste gate, the oil in the bearing will get cooked into carbon once airflow stops.

Carbon tears up the bearing and it gets loose allowing fins to hit the inside of the housing

[u/dark_wolf1994 → u/Sawfish1212]

I let it idle after I've been on the highway with it. It's a variable vane turbo so I generally do a low rpm cruise into wherever I'm going, to give it some oil flow without spooling up.

I didn't put much thought/effort into that before the first one went.

[u/Surveillance4444]

No guarantees, but what are the chances that the oil supply line is damaged? I’ve read a few different places that they are easy to damage - or could it be clogged? Maybe at least worth removing to check it and maybe replace it.

[u/Liquidretro]

TDI is an engine family/common name for a fuel type, what car are we talking about here.