All,

1998 P38 2.5DT. Newish comprosser, air spring good. A few day ago the rear, particularly the left rear i think started dropping very fast, like seconds when the engine is turned off. Today the "35mph" warning appeared, presume due to overheahed compressor. Reset all faults, loads of them and same problem still. Check air lines/springs with fairy liquid, all fine. When engine is switched off, the rear drops like a stone, along with multiple clicks from the valve block under the bonnet... Help me please!!!!!

D

Sounds like you've got a height sensor problem.

sounds like sensor fault or small hole possible in feed pipe. does corner drop on to bump stop or just fall low? Does your reader give you dynamic readings so that you can see what is happening?

I'd go for a sensor, but you should have a fault code for it.