Hi Guys,

Since I bought my range rover, the rear drivers side (RHD) air bag has been slowly going down over the course of a few hours. It pumps itself back up and drives fine with no faults shown. The only thing I had been told by the seller was two airbags had been replaced, one on the front and one of the rears. Invoices don't tell me which side. He also mentioned having replaced the valve block with a used one and had it professionally installed - receipt present.

After doing some extension searching with some leak spray, I tested all four air bags as best as possible including the hose fittings and couldn't see any leaks. I tested the cross link valves and found no leaks. I then tested the main valve block and found a tiny leak from a fitting. I nipped it up and the fault remained.

A couple of months on, I finally gave in and replaced the rear right bag thinking it must be leaking. It isn't. The car is still dropping on that corner in the same way.

My question now is; what should I be looking at? Rear cross link valve? Valve block? Is there a particular exhaust valve that releases air from this air bag?

Any help appreciated.

It has been known for the valve block to crack internally...it is only plastic which is a stupid material to use if you ask me!!!

Could sub in a known good one for a test and see if you get the same result.

Also, air bladders have been known to split where they fold over and are difficult to spot with leak detector. Have you tried extending the EAS to off road height, or even jacking the body of the vehicle on the sill jacking point and letting the bladder extended fully??

As above, my land rover indie told me only way to test air springs is to fully extend them and spray with soapy water, but it maybe a pinhole so may take some finding, but I don't think you should have any leaks on the valve block

thanks guys. As I mentioned, I have actually gone and replaced the rear drivers side air spring despite not being able to find a leak at any height with leak spray. This hasn't cured the problem or made any difference.

Just to further confuse things, every 6 weeks or so, it doesn't drop. I parked it up a week ago and it had dropped almost to the bump stop on that corner by the following morning as usual. I went away for a week, came back and there it was on the bump stop as expected. I started it and took it round the block, all fine, no errors it just took a while to inflate to normal height as though there was no pressure in the tank. I've left it overnight and this morning it is exactly as it was, not dropped at all.

Is this a valve block issue or a rear crosslink valve do you think?

Could be either....Spray leak detector on the rear CL valve and see what you get.

The Valve block has been known to crack internally....there was a post a while ago from a member with a name like RS2000CUSTOM or something like that where he had a crack valve block...I think there where photos as well...might be worth hunting that post down.

Thanks, I'll see what I can find.

I sprayed the crosslink and main valve block when I did the air spring but this was the connections of the pipes rather than the whole unit. I do think it is the valve block. After all, it was replaced with a used unit by the previous owner so no way of being sure it was a good one.