Bounder

So my rear air suspension dropped a few weeks ago and I got the "Stop, Car Too Low" warning. I drove the back roads home that night, about 6 miles and kept speed no more than 40-45 mph. Arrived home fine. I usually take the Expressway to work at about 70mph. Day later the rear air shocks rose up back to normal and the warning light was gone - it seemed to self-correct and running perfect. However, my check engine light came on and my guess it's related to my air suspension system somehow, still runs smooth and fast with only 55k original miles on the car. I thought it might be a faulty voltage regulator but unsure at this point. I know it starts right up and runs fantastically. Maybe a trip to Autozone for a scan is next. 2003 E500, one owner, 55k.

bmwpowere36m3

The two are not related… get the car scanned and replace the rear air springs (matter of time).

Bounder

Matter of time, guess wrong and throw away 50k miles of additional rear air spring use? Exactly what not to do. The check engine light went away too. Oh well.

bmwpowere36m3

I guess you know better… you’ll figure it out.

cetialpha5

They do fail with age and time, after all rubber doesn't last forever. You might have a leak. I'd look for it if you find it low again. The compress will bring it back up to the proper height, but it's not designed to run all the time. If you find it low too often, you should fix the leak otherwise you'll burn out the compressor and will have to replace the compressor too. As for your check engine light, no one has a crystal ball, get the car scanned, will probably tell you what the old code was. Everyone always acts like a code reader is the price of gold, but you can get a cheap one that reads MB specific codes very cheaply these days.


If you're too cheap to spend $61, at least spend $27 and get a code reader that will just read CEL lights, the one above will also read MB specific codes in addition to CEL lights, might even give you insight to you air suspension problem.

bmwpowere36m3

Part of my reply got cutoff and what I was going to add...

Often users struggle with Airmatic "leaks" and determining the source. The rear air springs are super common, at this age and higher mileage, and are impossible to check without removing. Replacement is preventative maintenance and will help cut down diagnoses time.

I agree with cetialpha5 a code reader should be standard today equipment for a DIY'er... like a socket set. A MB specific reader, example iCarsoft MBII is $200 and very good. Next step up would be factory scan tool clone, Xentry + Multiplexer for $600-1000.

People are just cheap... they don't even want to spend the $10-15 for factory service data, which is worth hundreds if not thousands of dollars in information.