Intermittent Cruise Control Operation, 1986 190E 2.3 5-Speed
 

A good buddy of mine has a 5-speed 190E from 1986 with 205,000 miles. It runs unbelievably strong still, and gets great mileage. He is experiencing some intermittent operation of the cruise control system. When he flips the stalk up to accelerate the car responds and accelerates. Some of the times when he lets it return to its normal position after reaching the desired speed, the unit fails to take over and control the car's speed. When this happens he can stop the car, shut it off and restart it, and then the cruise usually works. Is there a sensor or some feature of the system that is dirty or needs adjustment? Any clues would be appreciated. Thanks, Jim

You need to have the cruise checked with a cruise control analyzer to be certain of the problem.

Hey Jim. Or swap cruise control amplifiers with him and see if the problem goes with the amplifier or stays with the car. I have the same car as your friend, and its cruise control only sometimes works and sometimes when it is working it stops working. I want to get a new amplifier, because when I swapped my amplifier out with a friend's it worked and when I put mine back in it did not work. Don't try opening the can; there's nothing you can fix without a tester to tell what is going on, and some places that accept back the old unit with a core charge will not take it if it's been opened. Richard

Pls see MBCA info.
 

Hi Jim,
Though I have been a ROM, I am a new (registered) here.
I think the following information is helpful for you.

http://www.mbca.org/MBCA_Troubleshooting_cruise_cont.htm

I own two 190E 2.3-16Vs. One of them that I have owned more than 10 years had a same problem. I opened the amplifier and found a crack at solder joint. So I fixed it but it was not enough for my amplifier. A lot of electrolysis condensers are used on the board of amp. That kind of condensers are usually exhausted in 7 to 15 years depend on the environment.
I changed all the electrolysis condensers that cost only $15. I think you can purchase that stuff at Radio Shake or like that. (I�fm not sure.)
My amp was fixed in that way. I hope it would help you. Good luck!

Shinji Shimizu