Ok here goes. Thus may be quite a long post but I want to give as much info as I can in order to get the best responses. I apologise in advance.
A few weeks ago I had some work done on the fatty but not related to my issue. Due to problems at the garage, the car ended up on a 4 poster ramp with the wheels off for nearly 2 weeks, with the suspension hanging. The day I go the car back everything seemed fine. I ran the EAS through all its heights a couple of times with no issues. I drop the car to access when I park it up. The following morning when I started it up and asked for normal height I got the message "Vehicle Lifting Slowly". Not too bothered as I've had this once or twice before and it's always been a 1 off. Once the car had lifted it would move through the other heights with no messages. It does it every time the car has been stood for a few hours. I have had my code reader plugged in bit it isn't showing any problems. The car is not losing height on any corner. Now it is showing the lifting slowly message when trying to go from normal to off road height. Initially I suspected the compressor ring and filter dryer as live data shows the reservoir pressure only rising slowly when it is running. Over the last couple of days I have noticed a feint hissing coming from somewhere around the front wheel but I can't pin point it as yet. It seems to be there for quite a long time - 90 mins or so - but again the car is not dropping. I have not noticed this hissing before but there again I haven't needed to pay so close attention to the EAS. And today I had the message "Vehicle will lift when the system cools".
Am I correct in my diagnosis, and does anyone know what the hissing could be. Thanks for reading, and thanks for any views.

Hi,

Had a similar situation on mine - it would hold height but if i tried to change height it would lift slowly and the compressor would over heat (@130c if I remember) - Could not find the leak and had to pass on to my indi.

Turned out the blue supply pipe had a pinprick hole - where it had rubbed - indi replaced @ 2cm of pipe and all good.

Sorry can't remember where it rubbed but if you can get underneath you may be able to follow it back from the compressor.

Cheers

Simon

Interesting Simon. Thank you for the information.

and may possibly be "before" the valve block, which is why you get no height drop. .
Experience is the only genuine knowledge, but as time passes, I have forgotten more than I can remember
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Follow the pipe from the compressor to the tank and see if you can hear any leaks when the compressor is running, by dropping it down and asking it to raise to the top. Ears are the best tool.

If it's lifting slowly it means that the reservoir isn't up to pressure, but as Joe90 says if it's not dropping the leak is likely between the compressor and the valves somewhere. You can buy straight connectors which fit the pipe, so it's possible to chop out the bad section and splice in a new bit, or if it's a pin hole then just cut the pipe at the hole and put a coupler in. There is nothing that can't be fixed with a hammer😜😜
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Joe90 wrote:

and may possibly be "before" the valve block, which is why you get no height drop.

Found the air leak this morning. It is actually the reservoir! New one on order from Dan. Let's hope it's as easy to swap as it looks. Thanks for the thoughts, they did lead me in the right direction.