I am new to the world of the Volvo. Armed with the Haynes and having searched this forum, I have been unsuccessful in finding a commonality of the tachometer and speedometer.

Symptom: Engine running, car not moving, the speedometer and tachometer move up and down with engine acceleration/deceleration. This has happened since I replaced the coil, fuel filter and power steering rack lines. Though I have no reason to suspect the latter two as being involved, the coil may be related. My reason for stating that as a possibility is I replaced the failed coil (resistance testing results) with a generic coil.

What I Have Checked: Charging system output is 13-14 volts with lights & fan running. Cleaned and replaced some grounding points in the engine compartment.

Past Symptom: When applying the brakes, the bulb failure light would illuminate yet brake lights are working properly.

Present Position: Stumped.

Thanks,
Steve