Fuel Injector Replacement: Tips & Experiences

Hi,

My Golf (AFN engine with auxiliary control unit) had its first new injectors installed last Friday at 132,000 km.
The reason was the excessive black smoke produced at full load. I wanted to see if that would be reduced.

The nozzles were easy to remove and weren't stuck or anything like that. Only the small pieces of tubing from the return line were very brittle and practically fell apart.

The soot is almost completely gone now.
It's actually like it was when I first bought the Golf.

It might help someone whose TDI is producing a similar amount of smoke.

Greetings,
Thomas.

Do you notice a faint ticking sound when driving at half throttle, around 1700 RPM? It's very quiet, and mostly audible in the engine compartment.

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

'cu' is a Spanish abbreviation for 'con usted,' which means 'with you.' It is often used in online communication to indicate that the sender is available to chat or talk.

Here is an example of how 'cu' might be used in a conversation:

Person A: 'Hey, I'm bored. Want to chat?'
Person B: 'Cu!'

This means that Person B is available to chat with Person A.

'Cu' can also be used to indicate that the sender is thinking about the recipient. For example, if Person A is thinking about Person B, they might send a message that says, 'Cu.'

In general, 'cu' is a friendly and informal way to communicate with someone online.

Hello...

Regarding the vacuum pump: What exactly does the vacuum pump do on the side of the cylinder head in your setup? Is it also directly connected to the camshaft in your case?
Die Pumpe tickert/klackert nämlich bei mir, meine das Geräusch wird lauter. Normal ?

Best regards, Rainer.

Hi Passi,

Okay, so you mentioned that you know the sounds of your car very well, and I think mine sounds different than it used to.
Unfortunately, I can't really describe exactly what "different" sounds like.
Okay, but when I drive home later, I'll pay attention to that and write down my observations tonight.

Otherwise, the engine is running much more smoothly again.
When you suddenly release the accelerator, it no longer jerks.
(The nozzles are probably no longer dripping.)
The old ones were quite "charred" and already had a slight bluish tint.


See you later.
Thomas.

Hello.

The only thing I've noticed is that the engine is noisy and misfires during the cold start phase, but it runs more smoothly once it's warmed up.
It ran quite hard at first, even though it was warm.

It's difficult to pinpoint the exact source of that ticking or clicking sound. We would probably need to park our cars next to each other and compare them.
I think that the subjective perception of each individual plays too large a role in this.

Perhaps it's just a normal sign of wear and tear.

Well, in that sense.
Thomas.

@rainer... I haven't looked at that yet... but could it really just be due to the nozzle replacement I did? I mean, anything is possible, I know...

It would be interesting to see.

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

'cu' is a Spanish abbreviation for 'con usted,' which means 'with you.' It is often used in online communication to indicate that the sender is available to chat or talk.

Here is an example of how 'cu' might be used in a conversation:

Person A: 'Hey, I'm bored. Want to chat?'
Person B: 'Cu!'

This means that Person B is available to chat with Person A.

'Cu' can also be used to indicate that the sender is thinking about the recipient. For example, if Person A is thinking about Person B, they might send a message that says, 'Cu.'

In general, 'cu' is a friendly and informal way to communicate with someone online.

Hello.
I'd be interested to know how much it costs to have some fun with those.
'It's possible that the injectors are the problem, as I also have an AFN engine with 132,000 km and it's producing soot.'
at full load...
I heard that the fuel injectors are not exactly cheap on Audi .

Marco Brill.

Hi Marco,

It depends on how and where you buy them.
You actually have two options. You can either buy them new and pay the full price, or you can buy them as a replacement.
That means you're getting new nozzles, and VW is taking back the old ones.
Then you'll pay around 76 euros for a nozzle. The one with the needle lift sensor is a bit more expensive.
I haven't received the invoice yet, but I should get it in the next few days. If there's interest, I can post the exact prices then.
You can really save a lot on workshop costs by doing things yourself.

You could also order some on eBay or similar platforms, as they sometimes go for really cheap prices. I'd say around 150 euros.
However, you will also be taking on more risks.

Just to clarify for everyone, the black smoke coming from my car isn't completely gone, but it's significantly better. Before, when I pressed the accelerator, the cars behind me would create distance, because there was a large cloud of black smoke visible behind me.
"Now I still see some small puffs of smoke, but those are probably a.) deposits and b.) it might also be due to the auxiliary control unit."
To completely eliminate this issue, I would probably need to have the boost pressure increased, but I'm not sure about that.
If I drive at full power for just a few minutes, you can hardly see anything anymore.
I would definitely do it again, if only because of the jolts caused by nocturnal emissions.

See you later.
Thomas.

I can only report the same thing... My car produces less soot, but of course still a lot, because my catalytic converter is empty. (I didn't feel like paying 600 marks for a new one back then, so I just had it removed).

But otherwise, I've only observed positive things. Just that annoying ticking... it's driving me crazy.

Oh yeah, the white smoke at startup is still there, which is annoying. But I'm still hoping that the seal for the ESP will fix it.

I'll keep you updated.

hehe..

Hello,

I can only confirm the experience with the fuel injectors. I have replaced the injectors in several TDI engines (G4/Passat/T4) with mileage between 120,000 and 140,000 km, and the results were consistently excellent. Even if others disagree with me here, I remain convinced that...
Fuel injectors are wear parts. This has always been the case with non-TDI diesel engines, and I don't see any logical reason why it should suddenly be different with the highly stressed TDI engines. I can imagine that the common rail (PD) injectors are even more susceptible to wear due to the higher pressures, and these injectors are very expensive.
The injectors for the VP-TDI engines are available as Bosch replacements from reputable parts suppliers; you don't necessarily have to go to VAG. I paid between 250 and 300 euros for a set!

Regards,

Jürgen.

Jürgen wrote:

... Even though others may disagree with me, I still maintain that fuel injectors are wear-and-tear parts. ...

I said something similar earlier this year, and people didn't believe me then. But it's good that more and more people are starting to agree with that statement.

Thank you. I do not object!