Timing Belt Replacement: Cost & Procedure

hello...

I finally managed to change the timing belt myself on my Golf III with the AFN engine... it should be replaced at around 106,000 km .

Okay, so here's my problem: After I did everything correctly, the car went to the diagnostic tool for ESP adjustment. I followed the diagram precisely and got the value almost in the middle of the permissible range (before the change, it was much higher than allowed, but according to the forum, that wasn't a problem). Anyway, I did a test drive... I got on the highway and accelerated. Then, around 3500 RPM, I took my foot off the gas and let it coast because someone was slowing me down. Then I pressed the gas again, but the car wouldn't accelerate. Suddenly, I saw a huge wall of fog in my rearview mirror. After 3-4 seconds, it started to accelerate again... I got off the highway and drove through the city towards the garage, and the same thing happened there... I shifted to second gear, let it drop to 2800 RPM, and then pressed the gas, and there was the fog again. Cars were keeping a large distance behind me .

Anyway, I've now managed to get the pump working again outside of the specified range, and everything is working perfectly.

Can someone tell me what's going on? Or what happened?

Hello,

Quote:

I strictly followed the diagram

.
and what about the text? *g*
Did you really read the values for the diagram in the default settings mode?
Please send me a Screenshot of the VAG-Com settings window, showing the values you have set. You can leave the ESP as it is.
[email protected]

TIP: To take a Screenshot, press the 'Print Screen' key to copy it to the clipboard, then open Paint and go to 'Edit -> Paste'.

Best regards, Rainer.

I, of course, also adhered to the text .


Do you mean a Screenshot of measurement group 000? So, what data is currently in it... I'll get that to you as soon as I'm back in the garage.

BlauBaer wrote:

Do you mean a Screenshot of measurement group 000?

That is, what data is currently in it...? I'll get it to you as soon as I'm back from the garage.

Yes }

Sent the Screenshot...

I hope you can make something of it...

best regards, BB

Hi,

Okay, so the Screenshot shows the current settings, and with these settings, the car is working fine, right?



Injection start (value 2 at fuel temperature 9) according to the diagram:


Hmm, that's very suspicious, to be honest I'm at a loss. If I were you, I would simply adjust the settings so that the target values for the injection quantity can be reached, and then continue to monitor the situation (in case any damage to the injector control valve or the injection quantity control of the injection pump becomes apparent later).
I have one more suspicion: Is it possible to connect the two-pin connector of the needle lift sensor with the wrong polarity?

Does anyone have any other ideas on how to explain this behavior?

Best regards, Rainer.

Rainer K. wrote:

Does anyone have any other ideas on how to explain the described behavior?

Hello.

If the pump needs an "early" adjustment, my first thought would be that the active adjustment range in the direction of "early" is no longer sufficient.

There used to be something like clogged fine filters that could disrupt the pressure conditions in the injection molding system .

Or a transition resistance between the motor control unit and the injector control, which limits the maximum current = adjustment range.

So, the Screenshot shows the current setting, with which the car is running okay, right?


Yep... that's exactly how it is...

If I can manage it, I'll connect a laptop today and check the data while the vehicle is running. That way, I can see if the desired and actual values match.

Regarding the plug... I'll take a look. I haven't removed it myself, though. I have no idea about the previous owner.

There used to be something like clogged fine filters that could disrupt the pressure conditions in the injection regulator.

Or a transition resistance between the motor computer and the injector control, which limits the maximum current = adjustment range.

Is there a way to clean it, or should I just buy a new one?

What do you mean in the context of transition resistance?
So, it's probably some kind of electronic problem, right?

BlauBaer wrote:

Quote: There used to be something like clogged fine filters that could disrupt the pressure conditions in the injection regulator. Or a transition resistance between the motor computer and the injector control, which limits the maximum current = adjustment range. Is there a way to clean it, or should I just buy a new one? What do you mean in the context of transition resistance? So, it's kind of an electronics problem, right?

Hi.

The injection nozzle restrictor is located in the pump, where the cable enters at the "bottom."

I don't know what it looks like when it's disassembled there, or exactly where the filter is located.

Regarding the contact resistance: yes, it's an electronics or cable issue.

hello,

I also replaced the timing belt and adjusted the pump.
I'm experiencing a similar problem. Whenever I drive with the Pbox, it produces much more smoke than it did before the change, and it's also not achieving the same acceleration times.
Should I perhaps move the start of the injections forward? Or are there any other possibilities?

Skoda TDI 110/140 hp, engine code AHF, manufactured in 1999, 65,000 km.

tino wrote:

Every time I drive with the pbox, it smokes much more than it did before the change, and it also doesn't achieve the same acceleration times anymore. Should I perhaps move the start of the injections forward? Or is there another possibility?

Hi Tino,

Is the belt definitely positioned correctly (and not off by even one tooth...)?

Did you loosen the camshaft gear?

By how much did you adjust the pump setting?

Have you ever done a test drive with monitoring of the injector control pressure? What were the results?

hello,

I changed the timing belt together with a VW mechanic.
'There's a new specialized tool for the camshaft. You just need to remove the vacuum pump and attach the tool there, and then secure it. He said everything is precisely adjusted. We also rotated the engine twice, and everything still lined up correctly.'
The camshaft wheel was angled to allow the belt to go up and over it.
The pump started slightly too early. At 140°C, the injection timing was at 140 degrees, which was rotated 1/8 to 1/4 of a turn later to 48 degrees.
Subjectively, the first ride before adjusting the pump felt a bit better (it might have been an illusion, as it was at night), and there was also 'soot.'
test fart, no.
How do you mean that, regarding monitoring the injector control voltage using a VW diagnostic tool?

Thank you. Best regards, Tino.

Hello,

tino wrote:

...just remove the vacuum pump and connect it there, and check it. He said everything is properly adjusted; we even ran the motor twice, and everything was still working correctly.

It's good that the camshaft was stuck, but was it also the crankshaft?
Set the crankshaft to top dead center (TDC). There's a mark on the flywheel, and a plug on the top of the transmission. Remove the plug and find TDC.
Then, disconnect the vacuum pump from the camshaft. On the engines I'm familiar with, there's a slot, approximately 3-4mm wide, that must be perfectly aligned with the cylinder head. If a VAG component was attached there, there should also be a marking.

Best regards, Rainer.

Hello,

es ist unbedingt notwendig die Nockenwelle mit dem Abstecklineal zu fixieren, da das Nockenwellenzahnrad nur auf einem Konus sitzt und gelöst werden muß! Das war übrigens schon beim ersten Golf Diesel so - das Lineal ist bis zum AFN sogar das gleiche, beim AHF habe ich mir eines angefertigt aus Winkeleisen da bei diesem Motor der Schlitz in der Nockenwelle parallel zur Zylinderkopfkante liegt - beim AFN liegt er höher. In den gängigen Reparaturanleitungen sind sogar Zeichnungen dieser Werkzeuge. Den außerdem benötigten Dorn zum Blockieren des Einspritzpumpenrades kann man auch durch passende Bohrer (Schaftende) ersetzen. Das mehrmalige überprüfen der Einstellungen nach Durchdrehen des Motors (mit Hand) ist unabdingbar. Ein Diagnosetester(tool) braucht man nacher zur dynamischen Einspritzzeitpunktsprüfung. Hierbei wird im Grundeinstellungmodus der mechanische Anschlag in der EP überprüft in Abhängigkeit von der Kraftstofftemperatur. Man braucht dazu die Diagramme für den jeweiligen Motor. Wenn der Wert nicht erreicht wird muß je nach Motor/ESP-Version entweder die Pumpe verdreht werden oder das Pumpenrad auf der Pumpenwelle verdreht werden (Vorsicht! Dehn(screws!).

At my wife's Passat (AFN), a VAG dealership had replaced the timing belt about 3 months before we bought it. However, I later discovered that the camshaft was misaligned!

Regards,

Jürgen.

Passat (AFN) Golf (AHF)

tino wrote:

How do you mean that regarding monitoring the injector pressure using a diagnostic tool from VW

?

Hi Tino,

Take a look at the technical article on pump settings .