TDI Compression Loss: New Engine or Problem?

Hello everyone.
And first, an apology if this has already been written and I haven't seen it.
I found it.

I own an Audi A6 2.5 TDI with 110 horsepower, manufactured in August 1998.
The machine has now run for 370,000 kilometers and has been working like a clock. However, for about 4 months now, it has been experiencing some slight starting problems.
'When the temperature is below 0 degrees Celsius, I have to crank the engine for a longer time before it starts. But once it starts, it runs perfectly.'
Good morning, no problems so far. The car has now been to the Audi dealership five times.

Workshop visit one: new battery, €130.
Werstattsbesuch zwei: eine neue Glühkerze 54€ incl. Einbau
Workshop visit three: Diesel pump adjustment, €60.
Workshop visit four: verification of certain dates, €90.
Workshop visit five: Compression test. The highest reading was 8.2 bar (?), and this was consistent across all five cylinders.

The workshop foreman told me that I need a new engine and that I should expect to pay around €5000.
It all seems a bit strange to me.
Just before the problems started, the car was in the workshop for an inspection. The timing belt was replaced.
Three simmer rings on the engine were replaced.
Two days after I had the car back, I noticed an increased oil leak. The cause was that the installed oil seals were defective, and they were replaced (under the parts warranty).
Two days later, the belt for the diesel pump broke (€195).

Now, to my question: Can anyone offer a suggestion, or has anyone else experienced the same problem and found a different solution?
found during the recommended engine replacement?

If it's an Audi workshop, they should be able to find the problem.
The 8.2 bar compression reading is incorrect; there must have been a mistake, or they gave you the wrong values.
The wear limit for diesel engines is already at 19 bar.
If the pressure is actually only 18.2 bar, then the engine is likely severely worn.
and also have difficulty starting. In that case, the workshop would be right!

I checked again.
The following expressions are available for audio output:

Cylinder 1: 7.6
Cylinder 2: 6.9
Cylinder 3: 7.4
Cylinder 4: 8.2
Cylinder 5: 8.0

The printout also indicates that the minimum target value is 24.
According to my limited understanding, with such values, the car should not have the same performance as it always had (if it manages to start ).

Didn't we already have a similar problem with a timing belt that wasn't installed correctly, since the issue only appeared after the workshop had replaced it?

I completely agree with Stef; 8.2 bar is impossible. At that pressure, the vehicle absolutely shouldn't function at all.
You can roughly test the compression yourself. So, using the "Hoppeltest" described by Ulf in the technical articles, you can at least determine if the compression is uniformly high across all cylinders. Please read about it. Otherwise, my strong recommendation is to take your car to a different workshop, perhaps a Bosch service center, and have them test the compression.

Considering your mileage, it might be worthwhile to browse through the forum to get some information. After that, you can probably change the spark plugs yourself and save some money.

You were faster.


In my opinion, these values are not sufficient to run a diesel engine. Even if there were a "1" in front of them, it would still be too low.

Hi,

That reminds me of something...


/viewtopic.php?t=3336

... and there was also a workshop that was too incompetent to measure the compression properly.

There was also talk of oil coke in the intake manifold.

EDIT: If the timing is incorrect, open valves (or even valves that are already bent!) could affect the compression readings.

I'm going to stop by a Bosch workshop soon and explain my problem. Let's see what they have to say about it.
But before I set off, I'm going to do the 'bouncing test' as described.
As soon as I learn something new, I will write it here.
But something completely different. Workshops are insured, right? If they made a mistake while replacing the timing belt, they would tell you. And if they don't, what's the point of going to another Audi workshop? They wouldn't tell me that a colleague messed something up .

Stef621 wrote:

They wouldn't tell me that a colleague messed something up

.
Don't tell anyone about the other .

The Bosch service center has no available appointments for this month.
I've just contacted Audi in Ingolstadt directly. I'm curious to see what they have to say.
Ah yes, that 'shake test' was good. The paper barely moved.