Over efficient Cruise Control

[How Much??]

1989 500 SEL 160k

Maybe its German over efficiency but my cruise control is very 'jerky'. If i set it at say a very legal 70mph it will certainly keep me at that speed but not with smooth braking/gas as I have experienced in more modern cars but in a very binary brakes on or gas on manner. Is this how it should be ?

 

[jberks]

Normally jerky cruise is down to a dodgy speed pick up. Not sure where it is on that model so it could be a speedo cable wearing out or an electronic pick up needing replacing.
The cruise won't put the brakes on though. Even my 210 didn't do that. My 211 does though.

 

[How Much??]

Many thanks - gives me a starting point for investigating. What a fun weekend I've got ahead then...

Cheers

 

[ant500sl]

Lots of connections on the linkage attached to the controller at the front of the engine. These can get sticky with years of dirt and cause the symptoms described.

A quick clean and oil may do the trick.

 

[Legoman]

i can confirm that age isnt an issue on the cruise control , mine is as smooth as a new car which is a credit to mercedes imo