One side was hotter or colder than the other side and I decided to replace the valve. I didn't know how to test it other than how it felt. If you do this, get ready to rumble with yourself. The 2000 model has FIVE hoses attached to it plus you have the auxiliary water pump attached to it. In the way is the AC can, the anti lock brake unit, air intake system and very little room to work. The only parts you can remove is the air intake tube. The five water hoses hooked to this part must stay on the part for removal and installation. Remember: Plastic parts are junk and brittle. Take you time with those both on the hoses and the electrical connectors. Mark all the hoses and you MUST put them on the new part exactly like you took them off. Once you get this part bolted back in, there is on way to adjust a hose. You can't reach it.
Cautions: Air in the coolant system must be removed on re-fill. I had a lot of air. If you don't remove it, you'll overheat the engine. Orings. Be absolutely sure you don't lose an oring on 3 of the hoses. It will leak if you don't have both of them.

NOTE: If you EVER wanted to change your sway bar bushings, this is your chance. You have to remove the control valve bracket to reach one of the bolts on one the passenger side and "wala" you can reach it. I changed the bushings while it was accessible. Next project: rebuild rear suspension. I'll replace all the bushings and upper control arms. The rest of the suspension is fine.

 

When I first brought my 03 home I changed mine too. It's a tedious job but its doable w/patience and time.

 

Two test methods here, post #2:

https://www.jaguarforums.com/forum/s...2/#post1714570



Courtesy of Gus, here's a good write-up of a DCCV replacement. For an easier installation, be sure to notch the mounting flange as he has suggested.

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