Got a A2 311 VSS signal. Also had issues with surging idle, coming up to 1500 rpm at times after putting in park. Should I look to replace the VSS? Everything but my speedometer works (fuel gauge, barely).

93 940 Turbo. Been having a rough idle past couple weeks, and had oil burn out exhaust coming to a near stop and speeding by a biker at 2k rpm. No smoke coming up to 2k+ rpm at regular drive. Just changed oil today, had same thing happen, and will change filter tomorrow (needed strap wrench). Any id...