In Reply to: Cruise Control lunges posted by Rick on June 28, 1999 at 18:06:03:
I believe I know what you are talking about. Next time you are driving on a highway (and there is no around you) spend some time watching your speedo. You may notice that when you car surges, you notice that the speedo needle dips momentarily. If it does, your problem lies in the speed sensor or the cable to the speed sensor. It is located on the front of the diff. The sensor briefly stops sending pulses which makes the computer think you are slowing down, which in turn convinces the cruise control that it needs to speed up.
That's my 2 cents. (and then some)
: I have a 1992 auto 525i which began lunging or surging with the cruise control set about two years ago. At first it was only once or twice an hour and they were weak surges. Lately the surges and become severe lunges about twice a minute in hot weather.
: The car will jump forward for a spit second and then let off only to repeat itself later. It is worse in hot humid weather. I live in North Carolina, USA where the summers can be very hot. I also have a problem with surging under acceleration without cruise control on.
: Does anyone have any thoughts regarding a solution....and/or a cause?