Cold Start Injection Value & Software Version?

Translated on 11-09-2026, 16:35.

Hi!

I have a few questions about the CAY(B), and surprisingly, there isn't much information available about it.

Let's hope that's a good sign.

- Does anyone know the maximum/minimum injection angle before Top Dead Center (TDC) that the fuel injector uses during a cold start (at minimum temperature) in a CAYB engine (90 hp, 1.6 TDI)?

- As far as I know, there have been several software updates for the CAYs since their release. Does anyone know the current software version and, if possible, when it was approximately released?

- Additionally, in some early CAYs, the MSG (presumably a component) was replaced during a workshop procedure. Does anyone know why this was done?

Regards,
Jan.

Translated on 11-09-2026, 16:37.

Hello,

An engine scan would be helpful (VAG part number from the engine control unit).

It should be relatively easy to determine the maximum possible injection timing using VCDS.
- With the engine cold, disconnect the connector from the coolant temperature sensor.
- Use VCDS to access the engine control unit and find the extended measurement block, specifically the value for the injection timing of the main injection.
- Start.

Best regards, Rainer.

Translated on 11-09-2026, 16:39.

There's a revised engine control unit (ECU) from VW. I'm not aware of any workshop campaign for the VW Polo CAYC. We have one of the early models (February 2010). The initial software was completely flawed, with poor throttle response, premature fuel injection during cylinder deactivation, and extremely harsh particulate filter regeneration, etc. The second update has been installed since the beginning of 2012, and the regeneration process is now more subtle. Problems with injector quantity adjustments and engine misfires are known.
A workshop campaign for 1.6 TDI engines can have many reasons. It doesn't always mean that a part is broken. It could be that Continental (Conti) has doubts or needs more information, etc.

The engines have been using something other than a Bosch control/injection system for quite some time. A sudden failure or problems would be extremely bad for VW, because the 1.6 TDI already had a predecessor, the 1.9 TDI, that was arguably too good.

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

"Hello Blackfrosch"

P.S.: I can check the software version.