Fuel Injector Calibration with Gauge

Hello,

I just checked the repair manual (for the AFN engine), but the measurement procedure for the fuel injection timing, which was used for the mechanical TD engines, is apparently no longer included. It can only be done with a diagnostic tool now.
Okay, here's the translation:

'Imagine you're stranded in the desert and your laptop fails. Can you still adjust the ESP using a multimeter? Does the old multimeter adapter work with the TDI ESP? And are there any adjustment values available?'

Hello.
Wolfgang.

Hi Wolfgang,

With my 1Z model, the Bosch service initially adjusted the pump using a pressure gauge and then verified it with a diagnostic tool. I believe the good old pressure gauge still has its uses.
I can't tell you any more details than that.

@wolfgang

I can only confirm Bertil's experiences regarding the 1Z. When I was looking for a timing light adapter, a Bosch master technician told me that they only perform the initial timing adjustment using a timing light.
However, as can be read in Hähnlein's mega cold-start thread, the dial gauge method is not the optimal approach. It's only a rough adjustment that works in perhaps 90% of cases. In my opinion, the precise adjustment can only be achieved dynamically.

Hello,

According to VAG specifications, a coarse adjustment should first be made using a timing light. Subsequently, a dynamic fine adjustment should be performed with the engine running using a diagnostic system.

Hi,
The target value for the mechanical adjustment is 0.7mm ± 0.02mm.

Best regards, Rudi.

You shouldn't venture into the desert without a simple multimeter. As described in the technical article, it allows you to adjust the duty cycle of the injection timing with sufficient accuracy.

Hello everyone,

Thank you for the many helpful suggestions. I still need to get an adapter. Just to be sure: does the old Matra 2066 adapter, which was used for the mechanical ESP systems, fit the AFN?

Hello.
Wolfgang.
syncro16 AFN

Wolfgang, syncro16 wrote:

Can the ESP still be adjusted using a timing light, does the old timing light adapter fit the TDI ESP, and are there any adjustment values available?

Hi Wolfgang,

I adjusted the pump on my 1Z using a dial indicator, and the values were completely off (compared to the readings from VAG-COM). Try searching for "white smoke" in the search function; there's a huge thread I started about it . I still don't know why the values differ so much .

Best regards, Christian.

joergs wrote:

but: as can be read here in Haehnlein's mega cold start thread, the dial gauge method is not the optimum. It is only an absolute, rough adjustment that works in perhaps 90% of cases. But, in my opinion, the exact adjustment can only be achieved dynamically!

...hey Jörg,

I overlooked you .