kittyandgary

About 18 months ago, I had done a complete purge of the ABC system with new filter and a magnetic filter added to the system. 12 months ago, I changed out all the accumulators and dampeners. There had never been any issues with the ABC function, just did it for maintenance ('03 model with 50K miles).

This summer, I noticed on two or three occasions that the front of the SL55 was sagging after 4-5 days of not being driven, and when the car was started, the red indicator came on for the ABC. Within a few seconds, the ride height was normal and the light went off. I assumed a small piece of debris was holding the valve slightly open. Hmmm - probably need to have the valve rebuilt this winter.

But, I tried another approach. For about the next 15 times I drove the car, after getting out of the garage and on the road, and with an engine rpm of at least 2500, I'd punch the ABC lift button twice for full rise, then in about 1 minute push again for full drop. Did this about 8-10 times as the engine and ABC fluid were warming up (ABC fluid probably at max viscosity). My thought was that this higher viscosity fluid just might dislodge the debris if it went into and out of the valve quickly.

Well, now for the past couple of months, there has been no more sagging of the front, even though the car has sometimes been parked for over 2 weeks. And, of course, no further red indicator of a problem.

I don't know whether this will be a lasting 'cure', but it certainly seems to be working pretty well to date! Just wanted to pass it on as info, so others who experience the sagging for the first time might want to try this 'in situ' repair!

Gary--

shardul

iTrader: (1)

Nice trick!

knowbenz

Good to hear that has worked for you. Hopefully it stays fixed. If not the rebuild is pretty straight forward

carguyshu

make sure you drain the fluid out of each strut with the little nipple in each wheel well. When you flush the system this fluid will remain there and old and the only way to get it out is by draining it from each nipple. The system will then at start up refill the struts with new fluid. The fluid in mine was pretty much black and in way worse shape vs the fluid that can easily be flushed.

kittyandgary

carguyshu,

Yes, I'd done all that when I changed out the dampeners and accumulators. When I first purged the ABC fluid, the fluid I removed was still green. I got a little bit of darker fluid, but not brown or black when I drained via the nipples.

The first sagging - which is no longer occurring - was observed about a year after the accumulator/dampener replacement and about 2 years after the fluid purge. I may at least replace the filter in the fluid canister again this winter.

Ejbrock

Ejbrock

Great write up! I will certainly try this technique when needed.

Thanks Gary

kittyandgary

I will add a PS:

I now continue doing this occasionally when I'm taking the car out for a drive. I believe 'exercising' the system a bit might help keep those valves clean!! I'll try to report back next spring after the car has been stored for 3-4 months, that will be the proof as to whether the valves are really clean (car stays up for more than a month without the engine being started).

carguyshu

It's within spec even on a brand new car for it to sag after sitting a couple days

kittyandgary

Well, I feel if the valves are perfectly clean and in good condition that sagging doesn't occur in at least four weeks, as that is usually the longest between drives during the 3 seasons. At least it has not on my '03 model until the episodes I noted above. Had the car 3 1/2 years, and it had sagged the second winter in storage (last year), but not the previous winter (3+ months of storage). I'll be interested in what occurs this winter during storage.

That's just my experience.