2000 Vw tdi p1557 persisting only uphill

[Jakub]

I have a 2000 Vw Jetta tdi
234,000 miles

Runs here at but the minute I go up a steep grade it goes into limp mode.

I have swapped my n75
Changed all vacuum lines
Cleaned the intake manifold

Is there anything I can look at before thinking I need to swap the turbo ?
The cartridge in the turbo has very little play and sound freely

Thanks

 

[IndigoBlueWagon]

Check the turbo actuator to see if it's working properly and smoothly. If it's original you may need a new one. Lots less cost and hassle than replacing the turbo.

 

[oilhammer]

Positive boost deviation almost always means you have a sticking turbocharger vane mechanism. You can try seeing how easily the arm moves on the VNT actuator, and that it returns completely to rest when there is no vacuum applied, but more times than not you'll need a new unit.

 

[Jakub]

Is there a cleaner that can be sprayed into the intake to try and clean the veins ?

 

[oilhammer]

Dear baby Jesus no. Do NOT try that.

 

[Nero Morg]

Some people try oven cleaner to clean the turbo on the car... I personally think that's a huge waste of time since you'll get less than half of the VNT mechanism. Your better off taking it off, and cleaning it. Or replace it. Also make sure the bushing for the vacuum actuator isn't all worn out.

 

[Jakub]

Does the whole turbo have to come out to clean out the vnt mechanism ?

See I have this feeling that when my dad originally tried cleaning out the intake he didn’t pull it off the head and some funk fell down into the valves which maybe could’ve gone thru the system and got stuck in the turbo? Bec the issues wasn’t there before ?

 

[Nero Morg]

Yes turbo needs to come off, sit on a bench, and then the bearing housing removed from the manifold. As for the gunk, anything is possible.

 

[oilhammer]

The issue may not have been there before because the engine couldn't breathe. Now that it can, it can spin the turbo. And now, for the first time in who knows when, it is able to get enough air through to over boost.

This is a pretty common scenario.

Replace the turbo, or, if you want to try, get it off and take it apart if you can and see if you can get it cleaned up and freed up and working again.

 

[IndigoBlueWagon]

How far have you driven it since the intake cleaning? You may find that with some long distance driving the fault code goes away as the turbo gets hotter than before and burns off carbon. I just had that experience with my car after replacing a leaking vacuum pump. It wasn't even causing any codes or performance problems, but it took nearly 1000 miles before the turbo was fully functioning again.

 

[steve6]

give'r the ole "Italian tuneup"

 

[BobnOH]

Have you checked the operation of the turbo actuator? It should move with little resistance. If it's sticky try to work it til it frees up a bit. Then check if it moves when the engine is started.

 

[Jakub]

You know when I’m under the car and use a might vac it seems to move really easily. Is there something else I can use ?

 

[Jakub]

I’ve driven about 400 miles since I take cleaning

 

[Jakub]

Is there anything they sell that can run thru the turbo system to free up
Junk in it ?

 

[Nero Morg]

Is there anything they sell that can run thru the turbo system to free up
Junk in it ?

No. You have two options. Both require taking the turbo off the engine and putting it on a bench.


One. Clean the turbo vanes yourself and reassemble.


Two. Replace turbo.


Any type of "cleaner" you run through the turbo is just a bandaid fix, and only cleans a small portion of the turbo. The amount of effort and time put into trying a bandaid fix is very not worth it.

 

[wonneber]

As mentioned above do not spray anything into the intake.

I would take the actuator off first.
It's a vacuum hose, 2 nuts, and an e-clip.

Once off you can work the arm going into the turbo to verify it moves easy through the entire range.
I've read some have cleared it by working it back & forth for a few minutes.
The turbo in my Tiguan was sticking a bit.
I ran down the highway at 3200 RPM for 15 minutes.
It seemed to heat it enough and clear what ever was going on with it.

Also check for rust inside the actuator.
There's a VW bulletin about it.

Before replacing the turbo I would take it off and open it to clean it.
It's not easy to open it and a torch may be needed to heat it so the housing expands a bit.
There is at least 1 post here how to do it, if not U-Tube.