So I've done pretty much everything I can to fix the issues with my compressor. I've replaced the filters and desiccant in my air dryer and I installed the new seals in the compressor. I'm still getting the suspension fault. I decided today to finally do the soapy water test. I turned the car on and sprayed the air dryer. To my surprise there was air dumping out of the 2 fittings at the top of the dryer, you know the red and blue one. The air isn't coming out of where the air hose is but instead where the fitting attaches to the lid. I know I've seen before where they sell just the lid and nothing else but now I can't find it. The other option is to maybe tighten the fittings. Is that possible? I've had this compressor out 3 different times now and I'm becoming a pro so if I can tighten them that would be an easy fix. I would prefer to replace the cap if someone has a link to where I can purchase one. Can someone please help?

 

You can replace the air dryer canister. I'd try british4x4outfitters or lucky8 perhaps.

 

Nothing on either site. I've spent hours looking at sites and either they do not offer this part or they are out of stock. There is a company that makes an aftermarket metal cap but I can't remember where I saw it. I think it was on eBay but I can't find it on there now.

 

These guys sell a cap, but it doesn't look metal:

Range Rover Sport / Land Rover Discovery 3/ Range Rover L322 2006-2009 | LandyAir

 

Also, if you get to the point where you decided you need a compressor, arnott sell the AMK for $699.

But before that, have you replaced the relay? When the compressor or dryer is failing it kicks on and off so often that it can burn up the contacts in the relay.

Also, maybe the hoses that go into the compressor aren't any good?

RQB500491 & RQB000423 are the two hoses at that end, I think.