Rough running 1.6 TDI Cayenne, constant injector failure

Hello!

I'm experiencing the following problem with a VW Golf 6 1.6 TDI 90HP CAY:

First, a cylinder stopped working on the highway. There was an electrical fault with injector number 3.
I exchanged it for a new one, and it worked again.

However, this one also broke down after just 2 weeks. I thought it might be due to the three old injectors, so this time I used 4 new injectors. Of course, I entered the correct values each time using VCDS and also performed a fine adjustment.


After that, I took it for a test drive, but after less than a kilometer, injector number 4 failed. Another electrical fault.


I've noticed that it has a rather uneven idle, especially when it's cold. And the throttle response is also poor at low RPMs.

My theory would be that perhaps the pressure regulating valve is causing these problems. Maybe the injectors are trying to correct this and, as a result, are reaching their limit.


Or does anyone else have any ideas?

What makes you conclude that it's really the case?
What are the injectors?
Error codes read? / Have you checked the error codes?

Of course, how else?

"Electrical fault in the circuit" is the error message.

The reason must be different if it's already burned through three of them...

Hi there,
Have you ever considered posting the original error message here along with an Autoscan report? The statement "electrical fault in the circuit" is a bit vague.
And does that include a VCDS license or a support key?
hg
Herbert.

Okay, I'll do it this evening.

The injector fault itself isn't the primary issue. There must be something else causing the uneven running and leading to the injectors failing three times.

Yesterday, I installed another working injector so that the engine would run, and then read the fuel injection quantity deviation. This deviation is particularly pronounced when the engine is cold.

Cylinders 1 through 3...
Cylinders 2 and 3, etc.
Cylinder 3: -2...
Cylinder 4 +2,...