I have a 91 camaro rs, with a 305. engine code E.
My speedometer quit working a couple weeks ago, but it occasionally works when i hit a bump pretty hard, any suggestions? Is this a cable driven speedo, or a sensor? can someone also help me out by telling me where the sensor/cable is located on the tranny? Thanks, Dustin!

 

on the 700r4 its on the driver side tail end of the trans. i think the 91 came with either one (electric and cable) so ull have to look and see if theres a cable or wires going to the trans..

 

At times on my '82 belinetta it sounded like a helicopter was above me. Cable finally
broke & the the check engine light came on. I need to replace cable as check engine
will stay on until I do! Only thing wrong w/mine - but it bugs the hell out of me...

 

Starting in 1990, the Camaro speedo is electric, no cable. The gauge cluster plugs directly into the dash, no pigtails or wire loom between the dash and cluster. Back of the cluster is covered with a thin flexible printed circuit board that connects all the gauges together and leads to the plug-in area. It could be that there is corrosion or a bad/cracked connection on that board. As primitive as it may sound, have you tried banging on the dash to see if the speedo jumps? Don't go animal like you're trying to flatten the dash. If the speedo reacts to your love taps, then look at the cluster for the problem. Otherwise, check the plug and wiring at the speed sensor on the trans for a loose connection or broken wire.
If something turns up to be bad or unfixable with your cluster, I just happen to have a complete 1991 RS gauge cluster hanging around!