I would deeply appreciate any help I can get with this issue... Was driving a long distance in my 01 Civic EX when the speedometer stopped working meaning it was not showing the correct speed. I figured electrical issues. Then the speedometer tack dropped and so did the RPMs tack. Battery light came on and after a few miles the car died. The battery was dead but with jumper cables connected would start so I decided that it was the alternator.

Saturday I put in a rebuilt alternator. Once it was in I drove it around the block and as I pushed the brakes the engine sounded as if it was speeding up and the speedo tack fluttered and bounced all over. I parked it and the alternator voltage reading was less than 12 volts. I figured bad alternator and got another one. Put that in today and it's the same problem. Everything is buttoned up properly on the alternator.

Please kindly give feedback or any ideas you can think of. Electrical issues is my next guess...

 

Has the battery been tested?

 

Thanks for your reply - I bought a new battery with a 5 yr warranty the day the first alternator was installed.

 

One of the small wires on the alternator needs to get battery voltage from the car when the key is on. On older models it was always black and yellow. The same circuit runs the speed sensor (thus your first symptom was no speedometer reading), it comes from a fuse under the dash.