Update for my 2001 1.9 dci Lag saga.
Valve working fine. Recently removed it to check and clean it. It had sooted up pretty quick, but carb cleaner dealt with it easily enough.
The reason I took it apart was I under the bonnet anyway sorting a water leak. I had been losing a fair amount of water and finally discovered a hole in the expansion tank!! So beware old lag owners. It may just be a pinhole leak instead something bigger if you lose water. Note. The hole in mine I believe, was letting air in as well as water out
Anyway after replacing the cleaned
and fitting new Expansion tank, filling and venting coolant for about an hour, lol. I can report that lag sounds, pulls and feels pretty good for its 179k miles now. And as a bonus I am getting just under 47 mpg at 70. Which is good as my commute is a round trip of 86 miles a day. Huzzah
I did read on an old thread that the
's may need to be cleaned regularly. I will keep checking and post any useful data.