Problems with the intake manifold pressure sensor on the AFN

Hello,

I hope I've chosen the right forum section here. If not, please simply move the thread to a more appropriate section.

Okay, now to my actual problem: my engine control unit keeps reverting to emergency mode, and when I read the error memory, I get this message:

00519 - Manifold pressure sensor (G71) 28-10 - Short circuit to positive - Intermittent.


I've been advised to replace the wastegate valve, which I then did. At first, the car felt like it had improved, but unfortunately, that feeling changed after a few kilometers.

I'm now seeing the error again, but this time the "intermittent" status is not being displayed.

Do you perhaps have a possible solution or approach to my problem, or any suggestions on how I should proceed? For your information, the car was out of service for several months due to an engine failure and then received a replacement engine (block and head). The auxiliary components were transferred from the old engine.

Thank you for your help, best regards!

Hi.

Have you compared the error message with the tip?

If you go to the doctor and tell them you have a pus-filled inflammation on your FINGER, they will probably walk out of the room, only to come back and cut your FOOT.

The intake manifold pressure sensor is located in the engine control unit (or, in the case of a Passat 3B AFN, possibly in the intercooler) and has as much to do with the turbocharger control valve as your hands have to do with your feet.

The solution is therefore to check the sender and possibly replace it .

Greetings.
martin

dieselmartin wrote:

Hi Have you compared the error message with the tip?

Yes, I did!

By the way, I also got the tip about changing the valve from the master technician at our VW dealership!

dieselmartin wrote:

If you go to the doctor and say you have a purulent inflammation on your FINGER, he will probably step out of his room, and then proceed to cut your FOOT.

The issue with the doctor is something very obvious, but unfortunately, things are not so clear with today's electronics!

You suggest checking the donor, which seems to be in good condition externally and has a correct appearance (integrated into the MSG). Are there other ways to check it myself, or do I need to have the MSG examined by a specialist?

Hi,

Yeah, those good old tips from VW . Sometimes, those guys give some really strange advice.


The individual components are available, but I don't know how to obtain them, where to find them, or how much they cost.

Do you happen to have a spare engine control unit (ECU) that you could temporarily connect?
You can also connect a VAGCOM and an LDA (Linear Density Airflow sensor) to it and compare the two pressure readings; you should see a noticeable difference just before the limp-home mode kicks in.

Greetings.
m;

dieselmartin wrote:

The nozzles are available individually, but I don't know how, where, or how much they cost...

Okay, I'll try to go in that direction! Perhaps someone still has a tip regarding this, and if so, they can feel free to share it.

Unfortunately, I don't have any more LDA models available, so I can't provide a testing option.

With the replacement control unit, I could check if anyone would be willing to lend me theirs, including the transponder, for a test drive.

Thank you in advance for your help!

Buying a sensor: "Quael mal" - this might contain something useful.

LDA: A flexible hose, a T-connector, and a barometer (0-2 bar) specifically for compressed air systems, ready to use.

Replacing the STG: Why transponders? What kind of tractor is it? "With my G3, I didn't have to replace anything, I just had to retrain the WFS."

m;

You're right, the transponder doesn't need to be there; I had a little mix-up. It's also a G3!

That idea about using LDA is a good one; I wouldn't have thought of that, but it seems doable.

.. But don't be alarmed. If you make it as simple as I mentioned, the pointer will flutter wildly because the air is pulsating strongly.

For a quick check of the maximum pressure, it's okay, because once the boost pressure stabilizes (which takes a bit longer with a single-turbo setup), the gauge needle will also settle down.

Before that, it fluctuates between 0 and 1 bar in sync with the cylinders.

m;

Okay, I might be able to get a control unit for testing, but there's a potential problem, although it might not actually be a problem; I'm not sure.

My engine control unit has the part number 028 906 021 FQ! The other control unit is also from an AFN, but it has the index "GN" at the end!

Now my question, can I use this or not?