New Audi 80 1Z 1.9 TDI smokes heavily and misfires

Good evening, everyone.

I've been thinking for a long time about whether to sign up here, but gradually I've realized that most of the diesel-related topics you find on Google end up here, with the diesel experts.

It's about a 1993 Audi 80 with the 1Z 1.9 TDI engine producing 90 horsepower.

The problem is as follows:

I recently purchased this vehicle because I wanted a reliable car for the winter, but now a number of defects have appeared.

The vehicle starts perfectly on the first try, both when it's cold and when it's warm.

I have a feeling that the car has been chipped, but I couldn't see any obvious signs of a 10ct tuning module or a power box at first glance. Where would be a possible location for installing these items?

Nothing like that can be seen on the pump. Sure, I can translate the text for you. Please provide the text you would like me to translate.

The vehicle is very responsive, but it produces a lot of black smoke when accelerating, mixed with a little white smoke. It's not burning water. The coolant level remains constant, and the vehicle vibrates significantly under partial load.

Here are some things I noticed (see the attached image).

The large hose in the green-marked area was completely torn and constricted on its underside (it has already been replaced).

The small hose in the red area was closed with a screw and leads to nothing (Where does it connect to, and could this be the problem?).

In the blue area, there is a connector without a mating part; it is a two-pole connection. I seem to recall that it came from the cable harness where the fuel injection pump is also located. (Where should the corresponding part normally be?)

In the brown area, there's also a tube that's simply clipped on the underside (what exactly is that component?).


What else did I notice?

Disconnecting the mass airflow sensor will not cause any change in engine performance. The turbo whistles quite loudly, and in my opinion, it has too much boost pressure.

I suspect it might be a power box, a 10-cent tuning adjustment, or something else entirely.


Could you please answer my question above? Questions?

Thank you very much, and I wish you a pleasant evening.

Best regards,

phanlezz

Hi,
"Red area = connection for pressure measurement; it is sealed with a blind plug, e.g., like a return connection on an ESD1."
brown area = magnetic valve for boost pressure limitation & valve for EGR (Exhaust Gas Recirculation). "Please take a better picture."
blue area = please take a clearer picture, otherwise it's not possible to see what's missing.
hg
Herbert.

Please remove the engine cover and take a picture, especially of the connector that goes to the VP37.

Hello everyone,

First of all, thank you for your responses.

@Herbert

What do you mean by the sentence "is closed with a blind plug, e.g., like a return connection on ESD1"?

I took some new pictures, but unfortunately, it's a bit difficult to take clear photos with all the hoses and cables in the way.

The photos with labels are things that immediately caught my attention. The other photos are simply for providing an overview of the connection points, etc.

I hope everything is clear.

I already ordered 4 meters of vacuum hose to replace all the hoses in the coming days.

Unfortunately, I don't have a good understanding of the engine, even though I drive a car with the AFN engine, which is similar to the 1Z engine.

I'm having trouble figuring out all these hoses, so maybe someone who owns an Audi 80 with the 1Z engine can provide me with some detailed pictures and information about the hose connections.



Best regards,

Okay, I'm ready. Please provide the German text you want me to translate.

dieselschrauber wrote:

/viewtopic.php?t=3101

Thank you! I had already seen the schema yesterday... I'm not really the type for "wiring diagrams," but then I'll probably have to deal with them sooner or later...

I will report .

But have you already connected the hose that usually goes to the compressor side of the turbo?
Is VCDS available?
Sincerely,

klahaui wrote:

But the hose that normally connects to the compressor side of the turbo, do you already have that on? Is VCDS available? Sincerely

Hi,

Okay, so I connected all the hoses in what I thought was the correct way, following the FAQ, and I believe everything is connected properly.

It feels more like it has around 90 horsepower now, so I think the protective mechanisms are kicking in again and the turbocharger boost is being regulated.

Currently, it's still producing a lot of black smoke (very heavily), but it accelerates normally. I suspect there might be leaks in the charge air system.


@klahaui

Unfortunately, VCDS is currently unavailable because my laptop is broken.

I'm afraid I can't quite picture which hose you're referring to right now.

Can you possibly narrow it down for me, perhaps with a picture or an explanation?

I'm not an expert in this field yet, but I'm always eager to learn more.

Greetings.

The 1Z engine being discussed here belongs to the original generation; it still has a mass airflow sensor and likely an electronic stability program (ESP) controlled by a potentiometer.
Your pictures are far too focused on detail. Please make the sections a bit clearer/larger, so it's easier to navigate.
Just to note, I drive a 1Z model from 1994, which is the second generation. Generation.
hg
Herbert.

Herbert wrote:

The 1Z engine being discussed here belongs to the original generation; it still has an air mass meter and probably an ESP (electronic stability program) controlled by a potentiometer. Your pictures are far too focused on detail. Please make the sections a bit clearer/larger, so it's easier to navigate. Just to note, I drive a 1Z model from 1994, which is the second generation. Generation. hg Herbert

Hello Herbert,

My Audi 80, which was manufactured in November 1993, was already part of the 1994 model year and the second generation. Generations belong.

The mass airflow sensor is installed inside the air filter housing.

Pictures follow the days... unfortunately, I haven't been able to post them sooner.

Greetings.

Hi,
According to the pictures, it looks like you have an air mass meter installed .
But that's not important right now; we want to help you identify the connections.
hg
Herbert.

Hello everyone.

Having once owned a '93 1Z engine in a B4, I still have some related documents.
The engine with the air mass meter - i.e., the pressure valve in the air filter - always has...
First generation VP37 with the potentiometer in the quantity setting mechanism.

Regarding jerking and black smoke:
I had that too, especially with chips .
If you were to replace those two EEPROMs with original ones, it wouldn't work.
Replacing the blue coolant temperature sensor is a common repair, as they tend to fail.
The coolant regulator/thermostat in the water pump is also a likely culprit.
If it doesn't get properly warm, it starts to stutter.
"Especially with CHIP, many things in the characteristic fields are at the tolerance limit, and then things start to go wrong."

Personal experience

Here's a diagram showing a vacuum sealing setup.

Regards, Mpire.

Mpire wrote:

Hello everyone. Having once owned a '93 1Z engine in a B4, I still have some related documents. The engine with the air mass meter - i.e., the pressure valve in the air filter - always has... First generation VP37 with the potentiometer in the quantity setting mechanism. Regarding jerking and black smoke: I had that too, especially with chips . If you were to replace those two EEPROMs with original ones, it wouldn't work. Replacing the blue coolant temperature sensor is a common repair, as they tend to fail. The coolant regulator/thermostat in the water pump is also a likely culprit. If it doesn't get properly warm, it starts to stutter. "Especially with CHIP, many things in the characteristic fields are at the tolerance limit, and then things start to go wrong." Personal experience Here's a diagram showing a vacuum sealing setup. Greetings Mpire

Hi!

Thank you, thank you, thank you!

I can do a lot with that... provided I find the time again .

"It gets warm, the temperature fluctuates between 90-95 degrees... the temperature gauge is pretty inaccurate in the 80s, but I could replace the sensors; I have another Audi 80 that I can use for parts, although it's a gasoline engine, but that shouldn't matter."

Okay, so let's open the control unit and look for bad solder joints .

Greetings.

phanlezz wrote:

Okay, so let's open the control unit and look for bad solder joints . Greetings

The control units of the first generation (1Z) in the B4 are typically all mounted on sockets. The two memory modules are simply plugged in.
If it's a production unit, there's a gray sticker with the part number and software version on top.

There were only two software versions available for the switch, one with climate control functionality and one without.
The automatic transmission was a newer feature, only available from the model year 1994 onwards.

Regards, Mpire.

Mpire wrote:

phanlezz wrote: Okay, so let's open the control unit and look for bad solder joints . Greetings The control units of the first generation (1Z) in the B4 are typically all mounted on sockets. The two memory modules are simply plugged in. If it's a production unit, there's a gray sticker with the part number and software version on top. There were only two software versions available for the switch, one with climate control functionality and one without. The automatic transmission was a newer feature, only available from the model year 1994 onwards. Greetings Mpire

Okay, thank you!

As far as I've read, the control unit is located somewhere near the glove compartment, or possibly behind it.

Greetings.

It's hidden under the carpet in the passenger footwell .