I've been having a problem with my cruise control on my '94 850 sedan (non-turbo). When I get on the interstate I set the cruise to 65 and within two or three miles it will disengage. Most times. Sometimes not. It normally will not reengage immediately. If I wait two or three minutes and try to reengage it, it will do so. Sometimes. Sometimes not. Once reengaged it generally works fine. Sometimes. Sometimes not and it will disengage in about five miles.

I had my mechanic replace the brake switch which fell apart when he removed it. It seemed to have solved the problem. For a few days. Then it started disengaging again. I had him to check the vacuum hose under the battery tray and he says it held a vacuum when he tested it. I also asked him to disconnect and reconnect the electrical leads to the control unit which he said he did. Still the problem persists. This morning I engaged it, it worked for about five miles, kicked out, and wouldn't reengage for about five minutes. When I did get it to reengage it worked flawlessly for 40+ miles until I got off the interstate.

Has anyone else had a problem like this? Any help would be greatly appreciated.

Thanks,
Jim