I have followed this forum for years having had a few landys in the past, normally I can find the solution but this one is bugging me.I have had my 1998 P38 for about 4 years and had the usual issues, EAS leaks and pump failure, overheating, saggy head lining etc all of which have been resolved and for the last 6 months nothing has broken or dropped off

However on Saturday the suspension went up to full height on its own whilst driving at 50mph and then the EAS dashboard lights were going up and down like a yo-yo. It finally decided to work normally after about 20mins or so, since then this had become the norm with the max ride height light flashing away and the pump running. You can sometimes manually put it back to normal road height and sometimes it does it itself. I have also noticed that sometimes the rear stays at full height giving the P38 dragster look. I took the pump and valve block off today and cant see anything obvious, all the airbags look ok and the height sensors are clean and tidy. I also changed the relays in the fuse box relating to the EAS and pump. Plugging the laptop in with the EAS software it doesnt show any faults, but if you try to decompress the springs with the software only the fronts go down. The only thing I don't have to try is the small controller board on the side of the valve block, could it be that at fault?

Any ideas out there.

It does sound like your driver pack could be playing up but also check the white connector blocks behind passenger side kick panel, these are notorious for getting damp and the pins either going rusty or snapping off altogether as mine did, ì would also check all connections in the EAS box too, make sure all pins in blocks are clean and tight plus check all earth connections too.
Hope this helps.
Paul.

Cheers for that, just quickly checked the connectors before it go to dark outside and they are nice and clean, thankfully Will check the EAS box tomorrow.
Andy

yep. sounds like either bad connections in LH Footwell, or failing height switch. . . .especially if the car raises on it's own.

There is a similar fault symptom, where the height switch suddenly shows it going for extended mode, but without height changes. In this case it's usually bad contacts between driver pack & valve solenoids.

Fitted refurbished valve block and known good driver board, plus checked all connections and earthing and put new medium in the air dryer. Been round the block and nothing odd happening so far but tomorrow will get a longer drive wiith a bit of a load. Will wait and see how it goes.