Passat 3bg AVF geht sporadisch aus | Posts 24+

Then the car would consistently perform poorly, and its performance would significantly degrade under prolonged periods of high demand.

Hello!

Hmm, he has power, and he also runs relatively smoothly otherwise.
I put in some extra effort today and replaced all the diesel hoses in the engine compartment with...
Replaced the transparent hoses and properly bled the system.

The diesel fuel flows from the tank through the filter to the tandem pump without any air bubbles, but exits the tandem pump with persistent air bubbles.

I'm completely lost now and I'm spending every day working on the car, tinkering, and testing things, and this has been going on for 6 weeks.
Today, I ordered a new tandem pump, gasket sets for the PD units, a screw set for the PD unit, a diesel temperature sensor with its bracket, and the original diesel hoses with the original hose clamps. I finally want to be done with this topic.
And above all, I want to embark on my trip to Spain with a clear conscience.

Edit: I also ordered a new DiFi without the "Knackfrosch" (a type of frog toy). Cars used to run without it, and I prefer it without this unreliable part.

Best regards,
Oliver

r28oli wrote:

I would then finally like to be finished with this topic. And above all, I want to embark on my trip to Spain with a clear conscience. Best regards, Oliver

"Go ahead and replace the wiring harness for the PD elements as well; it's not a big deal now. After all, you've already put a lot of miles on it, and the cables are exposed to oil and heat."
They can therefore become brittle quite easily. Since you'll be working on these components as part of your project, you might accidentally introduce a new problem, such as a broken cable.

Tip: When working on the AVF engine in a Passat, it's easier to access the wiring harness at the rear of the cylinder head if the tandem pump has already been removed. The space available for the splash guard is limited.

Regards, Mpire.

Thanks for the tip, but I actually replaced that about 4 weeks ago.
That was one of the first parts I replaced since the engine started acting up.

Perhaps the engine control unit (ECU) is malfunctioning.

Hello!

No, it wasn't MSG.
I replaced the tandem pump and the pre-charge pump, and I also re-sealed the PDE units all at once. Since then, it has been quiet.
I drove to Spain and back (4000 km) without any issues.

P.S.: I can't say for sure which part was ultimately the problem, as I replaced everything at once. But I no longer had time for experiments.

Best regards,
Oliver

Well, then he's passed the long-term test. I'm happy for you.
Thank you for the feedback!
hg
Herbert.

Since we're already talking about PDEs.

Was it easy to remove and reinstall, considering its age?

Yes, it was simple and easy to do without any problems.
I was worried while disassembling it that maybe the PDE had somehow damaged the head, but thankfully, that wasn't the case.

I'm not sure if they were leaking. The old sealing rings still looked good.
The only thing that bothered me was that the screws that needed to be replaced were so expensive.
I paid 87€ for the 12 stretch bolts at the dealership.

Sure, here's the translation:

"Best regards,"
Oliver.