I replaced the TD4 turbo boost solenoid. The person who wrote the original sticky post about it taking 15-20 minutes was writing in 2011 and his vehicle can have been at most 10 years old. Mine is 19 years old and it was no fun crawling around in...
Just incase anyone else has this issue in the future. I took off the plastic piece that was blocking one of the line which would normally be the turbo filter. I attached a hose and the filter and reattached the other hoses to the vacuum pump...
Mine does the same on one specific hump in the road that I would go through at 40mph usually. The answer has been to gently slow down to 30 while approaching the obstacle and then speed up again. Problem solved!
As stated. Vehicle has had a replacement engine (112k) and new Borg & Beck clutch.
Tyres are as new, well worth a look if you want a 5 door TD4 Manual.
https://www.ebay.co.uk/itm/317016824076
My 1st gear switch connector hadn’t been fully pushed home, probably because of a small piece of grit. Cleaned it all and like you, voila! HDC works perfectly.
Just to finish this off, the battery-disconnect-reset worked OK, And the radio was fine (no code needed), but after a week and a short drive with the rear window open, the cab switch for the rear window went awol again. I repeated the reset which...
@Kerlaan
Once I'd worked out where the switch was, I found nothing connected to it. There was a connector tucked neatly out of the way behind some fittings on the body nearby that fitted, so I tried it out and the system works perfectly now...