I am having big problems with the cruise control on my 1991 300CE (NOT 24v). If I can get it to work at all, it usually engages for about 1 second, then surges briefly and drops out very suddenly. Accelerate works fine. Sometimes it will work for a while, then it 'hunts' for a few seconds, surges then drops out.

Someone has suggested dry joints/bad connections on the 'computer' which controls it - problem is, I can't find it! The original article said it was under the carpets or in the side of the driver's footwell, but I have had everything out and there is NO control box, believe me!

It's a RHD model fro British market. Any advice on location/identification and how to cure the problem would be much appreciated. Thanks!