1991 Acura Legend

Transmission problem
1991 Acura Legend 6 cyl Two Wheel Drive Automatic 195000 miles

My speedometer jumps around or does not work. Mainly happens on the freeway. All of a sudden my speedometer will jump back and forth from around 120mph to 0. Sometimes the RPM's will be affected and the car will jolt. Any recommendations?
May 14, 2010.

Speedo is controlled by vehicle speed sensor and the VSS also interacts with the RPMs and tranny. If you are having issues with speedo and tach then the VSS will need inspected. Make sure wiring is good to it and check ground to speed sensor, should be next to throttle body.

May 14, 2010.