I don't understand anymore | Posts 16+

Deleted upon request.

Oh, sorry.

I meant EDS (Electronic Differential Lock)... my mistake, I read it too quickly... I had my neighbor's problem in mind, where his car with winter tires was jerking without actually engaging the differential. The car manufacturer's response was: "it's normal... there's a new software for that..." and that solved the problem (it wasn't a VAG product).

Regarding EDC (now correctly):
I have three engine control units (ECUs): two original ones and one completely different one from a Passat. However, all of them exhibit the same behavior. Even with a power box and tuning chip installed, the behavior remains the same – neither stronger nor weaker.
The parts around the engine control unit (ECU) that could be causing the jerking are a mystery to me, given the unusual symptoms. I would be happy if it's not the pump. However, it's surprising that the jerking stops when using a different pump...

Yes, the hysteresis test was supposedly performed - allegedly without any errors... (I wasn't present, and this test doesn't appear on the invoice from Bosch service). If the hysteresis is no longer correct, then the pump would have to be replaced anyway, right?

Deleted upon request.

Hello Diesel.Gustav,

diesel.gustav wrote:

My mailbox is currently full, so I would prefer not to establish email contact for the time being.

Ouch, well, I guess it's better this way...

Quote:

... If the hysteresis test was performed by someone who doesn't understand what they're doing, it's worthless. It would also be interesting to compare the hysteresis curves of your pump with those of the test pump that didn't cause your vehicle to jerk. ...

So, the technician at the Bosch service center seemed very competent, but he didn't want to "sell me" a new pump.
Unfortunately, the "comparison pump" is already installed in another car, and I have very little (or no) access to it anymore.

...

Quote:

Based on the additional information you provided, I would also suspect the pump. There might be an issue with the signaling system and control valve, which could be somewhat stiff, or a problem with the pressure pipe connection, or an interaction with other functions that are difficult to identify remotely. Regarding the "difficulty" issue, I have another suggestion, but I'd like to wrap things up for tonight due to the late hour. I'll get back to you about that in the next few days.

"That would be great! Thank you in advance."