Pretty sure that'll be the 'cancel' button, for cruise control & speed limiter

So...  After a few months, I finally had the time to try and fix this problem.

There are 2 switches on the transmission box. One is as the bottom of the battery and that is the reverse switch (Not the neutral switch I said on the above post), and the other is under the car... u need to lift the car up to see it, remove the plastic cover, and it's at the side of the transmission, in front of the radiator (kinda.    you will see it).

Replacing that fixes the problem.  That switch cost like 2–5 euros

PROBLEM SOLVED.

Thank you all for the support and comments trying to help me with this and I hope someone will find this very helpful and not go nuts
 

Hi All, does anyone know the part number for the rear window weatherstrip seals for a MK2?

Enter your VIN number on https://partsouq.com/ and you should find part numbers for your specific vehicle.

Thanks folks I appreciate the help and feedback . . .

I ran a search and looks like it does have a timing chain this year/engine. It just doesn't quite sound like a rattling chain to me but then I'm not an experienced mechanic. I'll have a read up on those stethoscopes sounds like a good investment.

I got some more history on the vehicle today, my Step-Dad purchased it virtually new with only 30k's. The noise started after the first service/oil change, he regrettably didn't follow it up under warranty. Ouch!

But as I say its been quite a few years since and now it's racked up over 200k's and the noise has remained the same/not got any worse. If it was a loose/worn chain thought it would of given way by now.

Ta,
Rich

When was the last time the Diesel fuel filter was serviced?

Apparently the filters were all done at the end of last year, and I think he tested the fuel pump, too.

It's still doing it... I'm still stumped!  🤣🤣