Turbodefekt: Causes, Symptoms, and Repair:(

hello

I bought a Volvo with a 5-cylinder AEL engine that's in a very bad condition. Now the question is, would replacing the turbocharger fix the problem, or are there more serious issues?

"First, I need a turbocharger, or at least a verschandeln installation kit (I would then, of course, install the good one in my TDI car and put the one from the TDI in my project car)."

It would be great if someone could help me diagnose my initial findings.

"After we had taken care of some other issues and spent a long time troubleshooting the immobilizer, the car finally started immediately with the correct transponder. It then sat stationary for a very, very long time. Before that, we had topped up the missing ~2 liters of oil. The hydraulics/valves sound a bit abnormal - although it's hard to tell if that's even noticeable on a TDI - but I don't think it's *that* bad."

* When we finally put the car in gear (automatic) and had to press the accelerator, the car was EXTREMELY smoking out of the exhaust - not blue or white, but I mean it was oil. That was somewhat expected. What was surprising were the noises - sometimes a very loud knocking (it sounded quite similar to starting spray/brake cleaner - you think the piston is about to come out).

Perhaps someone has a tip or information – could it really be a problem with the charger? Or something else? Regarding the noises?
Thank you very much.

Sure, here is the translation of the text from German to English:

"Hello"

Hmm, difficult.

What engine control units (ECUs) did Volvo install? In other words, can the boat's problems be diagnosed, for example, via a generic OBD interface, or did they perhaps install a VAG-specific ECU?

I see in your signature that you have two AELs, but is one of them not being used? If so, you could potentially swap parts between them.

Let's assume, for now (although I doubt it, given the history!), that the crank mechanism is still in relatively good condition.

First, I would check the basic things: tightness of the intercooler system, air filter, diesel filter, have the injectors cleaned, remove the turbocharger and check the shaft play, remove the valve cover for a visual inspection, and check the valve timing.

So far, it's just labor-intensive, but it doesn't cost much, if anything.

Is that box from Achmed (Kollegah, is everything okay, my brother said...) or where did it come from?

Okay, so I have two TDIs - yes - and the faulty one would be the third. I don't want to modify it too much, especially not the turbo. I wouldn't want to take apart a working car.

I'm already focusing on a faulty turbocharger; that was also the diagnosis from the Volvo workshop where the car came from. Why would they lie to me? If anything, they simply might not have known any better themselves...

Why do you think the crankshaft might be the problem?

"Diagnosing the control unit isn't a problem for me; it's a specific Volvo control unit, but I have the ability to read everything from it. It was definitely connected, but I couldn't even measure things like boost pressure; above around 1500 RPM, it was like the sun went down – pure fog."

gru

Okay, now disassemble the turbocharger and inspect it for any shaft play. Also, check the amount of oil that's accumulated in the charge air cooler (intercooler).

"Well, I would have expected that too."
"Just be careful that the turbo isn't forcing all the oil into the engine, as that would explain the smoke and the rough running."
How many kilometers has the broken one already been driven?
If you have the option, you can read the error codes, but I would really recommend doing that only after checking the intercooler and the turbocharger.
And maybe double-check the engine oil level.

I think the turbo is responsible for it. Well, there was an error code related to the turbo control valve in the error memory. I cleared that error, and of course, it hasn't reappeared since - so there's no real danger.
I think that's probably the next thing.

"Thank you."
Sure, here is the translation of the text from German to English:

"Hello"

Is that actually a VTG loader as well?
It's possible that, if something is wrong with the valve timing, the lack of boost pressure is due to the inability to properly regulate the airflow.

No, that's a wastegate turbocharger.

Then a non-closing wastegate could be the cause, especially if it's no longer being actuated. Check the hose connections.

White-gray smoke coming from the car = very likely a turbocharger issue. I experienced something similar a long time ago with a customer who wanted more power from a car with 400,000 km. }

@Rainer: But if it's so severe that you had to add 2 liters of oil, it almost sounds like the loader could eventually start running on its own because the combustion chamber is consuming the engine oil.

Correct