Xantia slow to rise

[BrianM]

I had to change the pipe going from the flow divider to the steering rack and since this the car is very slow to rise. ( 93 Xantia TD) Stop light goes off initially after 3 to 5 seconds but once I touch the brakes etc it comes back on. It seems however that if I turn the steering a couple of times all comes ok again. Anyone any ideas as to what has gone wrong?. All the spheres were changed about 6 weeks prior to the pipe bursting and the car was fine. Fluid level is fine, pump has 90K on it but was ok before also.

[jeremy]

I think the burst pipe has caused one of the sliders in the FDV to go to the end of its travel and stick there, providing max flow to the steering.
When the wheel is released the steering valves allow LHM to return to the reservoir. Turn the wheel and the return is cut off, pressurising the system, and high pressure LHM goes further down the system.
I had this problem with 2 FDV's on my TD BX and on the second one (which in fact came with the car) I found the system pressure relief valve which is situated under the middle cap on the side of the valve had been assembled incorrectly. It is possible that the burst has allowed a huge flow of fluid which has dislodged something which is blocking the correct operation or had jammed under this valve. I always wonder what happens to the bits of the filters which are often found to be broken when the FDV's are examined.
My symptoms - slow to rise, bad ride at time (car dropping) - light coming on after a couple of miles and going out if I could find a reason to turn the wheel and sometimes on changeing down a gear. car could be made to rise by turning the wheel a bit and holding it there. - Now - all perfect.
jeremy

[BrianM]

Thanks Jeremy,
Checked all unions again at the weekend, depressurised system etc, now it appears to be ok again, perhaps whatever went wrong in the FDV has rectified itself .