nsraja

2004 E500 Base with 130k miles here. Replaced both Front suspensions with Arnott suspensions at 110k or so. In the last 2k miles, I hear humming noise coming from the front at every stop signal. I can see the vehicle rising a little bit, not as much when you rise your vehicle with the riser button on the center console, but it does rise a bit I am sure about that. So I am suspecting the Arnott might be leaking air and the air compressor is constantly trying to keep the vehicle up?

I bought both my Arnotts at FCP Euro, so I can replace them in a heartbeat without paying any money (using their use it abuse it return it policy), just want to make sure it is really the Arnott suspension before I abuse their policy. What other things I should do before I jump into the conclusion of replacing the Arnotts again. (Yes FCP Euro return policy does really work).

FCPEuro

You would want to verify that your suspension valve block isn't failing. It's not uncommon to still have the the original valve block on an 04 and it could be leaking internally.
--Kyle

nsraja

Thanks Kyle. In fact there was a code stored that indicated something along the line (like line pinched to control resorvoir or something like that). The component name mentioned was actually the suspension valve block. I have another bigger problem with the rear airbags. I already bought two rear airbags (Arnott) from FCP Euro but just have not had the time to replace it besides I am in Kansas on temporary basis and the cold is making it worse on the suspension (as well as make it impossible to get under the car). Upon doing more research I am trying to figure out if it is the height sensor or the linkage that is causing the problem. Rear of the car sits on the tire in about two days when it is around 15F and when it drops to below 10F then it sits within a day or so. Last four days it has been in the high 40s and the car has not dropped. Not sure if it is the weather or the rear axle height sensor or its linkage to sway bar that has decided not to act up.

I am shaking my head in disbelief - how in the world a company like Mercedes survive. Living in fear what the car might do next is not I would call "luxury". I bought the 9 speed Odyssey recently and I dont really see a point in owning a Mercedes given the ride quality I experience with Odyssey.

F1Fan

it is the rear air spring leaking. Replace with Arnott and you will be fine.

nsraja

It was indeed the rear air spring. I went under my car, inspected the suspension height sensor, it is in a difficult reach location and the connecting rod (that some complain as badly rusted) looked like new. So I had no reason to suspect the height sensor. Replaced the air springs with Arnott springs I got from FCP Euro and the problem has not come back. The humming sound I get from the front (and the actual rising of the front at traffic lights) has not disappeared. Now I know how to replace all suspensions and all are from FCP Euro, if anything should go wrong I get to replace it for free. FCP pricing had always been competitive but in the last two months or so I see prices across the board have gone up by 5 to 10%.

Thanks everyone for the tips and thanks FCP for giving me the peace of mind.