Hello everyone,

Recently, I acquired a 2004 Mercedes S430 in excellent condition from a friend. The car boasts a mileage of 177,000 and has received meticulous care over the years.

However, I've encountered an issue where the rear end tends to leak down overnight or after a couple of days. Interestingly, when I unlock the car using the remote, the rear end pumps back up. Notably, when the car is in a lowered position, it remains uniformly low on both sides.

In my research, I came across information suggesting that if the vehicle is experiencing a uniform drop, the culprit might be the relay. Admittedly, my knowledge about the Airmatic system is limited, and I'm reaching out to seek your valuable input.

Could you kindly guide me on where to begin investigating and share any insights on potential culprits for this issue?

I appreciate your time and assistance.

Ron

__________________

Find the valve block on top or near the pump, use soapy water to look for leaks

__________________
I do not 'believe'. I have no use or time for this distraction. A'priori is antiquated furniture that clutters the mind and deteriorates society. Instead I investigate, research, scrutinize then choose from data what best serves as a suitable answer until a new idea or material is presented. Then I start the process again.

https://w220.wiki/Airmatic

Small leaks in the rubber airbag (i e. the spring/strut itself) are quite common as well. Spray soapy water wherever you can, and keep an eye out for bubbles.

__________________
TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth