I have a rattle type noise from the front top of my 1997 xk8 engine have change VVT solenoid still the same ideas and how do you check VVT themselves, for info it has 2nd gen tensioners

 

I would imagine it would set a code if you vvt solenoid was acting up.

I don't know how to verify a vvt solenoid, I guess if you take it off and power it on a bench you would be able to check for normal operation.

 

Solenoid a are working fine it's the main VVT unit I was wondering how you check

 

Thanks for welcome all, know I have the covers off and the tensioners are 2nd generation so they have been on over 10 years I would say so as the car is off the road at moment I'm going to do the whole lot tensioners chains and guides plus water pump then it's just the abs/ trac light to sort and she is back on the road so if anyone in the uk has a locking set for sale let me know

 

mctb - I've moved your post from the XK/XKR section to the XK8/XKR section for your MY as it will get better response/visibility.

regards,
Steve

 

I think you are smart going after a refresh of all the components. Did you ever find the source of the rattle? As for the VVT's, you can test them using 12v source to see if the activate. Most likely, they will. I have found, however, that they can lose their relative position of the pintle, and still "click" as you test them. With the VVT out, look at the position of the center rod in relation to the outer housing slots. (I wish I had a pic. It you can, compare a new one with each of yours). When they are in proper position, the center rod rings basically align with the rings on the outer housing. If you can see a mismatch, you may need a new solenoid. I doubt if this has anything to do with your rattle, but it is still a good way to check your VVT solenoids. Remember to "wind back" the VVT units when you put your chains back on. And, the drive sprockets on the crank are NOT to be aligned together. They are staggered. Pay attention when you disassemble!