A6 C4 Fuel Injector Pump Leak - Repair

Hi,

Now, not only does water get into the car during rain, but diesel also leaks out of the car even when it's not raining .

On the front of the ESP (at the bottom), there's a module that's attached/screwed on, and a cable goes into it. It seems to be leaking – there are droplets. Does anyone recognize this problem? Is it possible to replace a seal there?

Best regards, Kai.

Good day.
Are you talking about the nozzle for the injection molding machine?

The complete set of seals for the pump costs 12.50 euros at Bosch. I would probably end up sealing the entire pump anyway.
There are good instructions available in this forum for replacing parts. However, the high-pressure component and, especially, the flow meter require a certain level of skill.

Water in the C4? Where is it coming from? Is it the sunroof? The heater box? The C-pillar?

Hi,

I'm not entirely sure yet if it's the injector sealing ring. I'll try to locate it using a mirror and a paper towel.

Does anything obstruct the removal of the spray nozzle, or does anything get in the way?


Water is leaking from the window seal above the C-pillar (Avant). Silicone will be applied to the trim soon, and then this problem will be over .

Best regards, Kai.

Silicone reacts with acids. Because of this, the bodywork would corrode, so I wouldn't do that.
It's a good idea to remove the casing and see what's going on.

You're definitely going to encounter a lot of diesel vehicles.
I would remove the pump and place it comfortably on the table, then take my time and do everything carefully. That way, there's also less risk of losing anything.

Hello.

My VP37 injection pump failed at 150,000 km due to a leak, thanks to the previous owner (who used biofuel).
It started with the turnout machine - that electronic beast .

"The fuel injector was also a topic - it's very accessible from the front on the Volvo. I even got an O-ring for it, but tightening it firmly once also worked well."
Finally, there was intermittent but significant diesel leakage – very annoying. It was impossible to pinpoint the source. Therefore, it's best to either completely replace them or seal them – because if one side leaks, the next one is likely to leak too.

Good luck.

Sure, here is the translation of the text from German to English:

"Hello"

PS: I wouldn't use silicone either, I'd rather use something like Terostat - that's what they use for windshields.

Hi,

'So, it's leaking from the middle horizontal seal on the housing halves of the ESP.'
It looks like it's time for a round of BOSCH service.

Get a gasket for €12.50 from Bosch, and you can figure out the rest.
Sealing a fuel pump at Bosch probably costs around 550 euros or so.
I'm too stingy for that, so I'd rather do it myself .

I would have thought so too - but how do you readjust that electronic thing?

Do you mean the point machine?
Mark several spots with a needle and then put it back in the same place.
The setup is a bit tricky.

On the first attempt, my engine immediately revved up to 5000 RPM because it was misaligned by 1/10 of a turn.
I then adjusted it more towards 'less diesel,' and it worked.
I fine-tuned it using a slightly adjusted quantity setting, VCDS software, and a small hammer.
I would gently tap the MSW until the readings were perfect.
Target: 4.7mg/h at idle!
I set the injection start to '62'. It was a great value.

Edit: I just added you on ICQ!

Hello,

I've managed 300,000 km without using VAG COM, but it seems like the time has come .

What hardware/software/interfaces from this shop do I need for the AEL (presumably a specific application or system)? A laptop is already available.

Best regards, Kai.

You basically just need VCDS, a KKL interface, and a 2+2 adapter.

If you don't absolutely need to buy it:
I'm planning to drive from Kassel to Frankfurt soon. I want to visit my mother again. I could stop by and quickly help you out if you need anything.

'Wow, what an offer . I would definitely like to take advantage of that, even though I'm also interested in the VAG COM.'
I'm a fan of markings. Changing the Z-height also works well with them, as long as you're careful with the markings. But when I read about 0.1mm offsets and then wild effects, I get nervous.

I will definitely order the gasket set right away.

By the way, a non-cast engine block is also advantageous: the engine block does not rust .

Best regards, Kai.

Well, with a TDI engine, you can definitely tell if the timing belt is misaligned, either too early or too late. This has a significant impact on the engine's final power output.
With the VP37, you can notice incorrect settings in the starting behavior, throttle response, and sound when it goes outside of its operating range.

You can come by and see what's possible.
It is definitely practical to have such a diagnostic option .

Oh no - I haven't used ICQ in a long time - I'll remove that from my profile.

"You're right about adjusting the injection timing. You can often get a good feel for it and adjust it by ear. I always do it that way because software-based measurements are only possible when the engine is warm. When you're warming up the engine, you can usually tell if you're way off. Usually, it's not much off. Especially if you know your car."

Regarding the VP (vacuum pump), I'm having a problem where the fuel injector sporadically malfunctions, causing a momentary loss of power for about half a second. Everything is perfectly adjusted, which is why I want to rebuild a pump that I removed from another car due to a severe leak. I was thinking of trying to seal it myself and then having it adjusted on a dynamometer at a Bosch service center. However, if, as you say, marking the adjustments is a good way to do it, that's worth a try, especially since I can measure the fuel injection volume using software, assuming that's an accurate method.

Best regards,

As I said,
Okay, next week I'm heading towards Frankfurt. I can explain everything in more detail then.
It's really not much work on the 5-cylinder engine.
I'm so annoyed that I sold my old car. My current V6 TDI is driving me crazy, and I don't see a solution in sight.

Hi,
I ordered a sealing ring. It should arrive shortly.
How do you actually get that incredibly difficult triangular screw off?