I have a 2003 6spd with a 0483 code showing up. The speedometer jumps around more so at a idle. The speedometer may go from 20mph to 100mph when at a idle, but when you are going down the road it is not as bad. I was just wondering if the two are linked together or if I need to look some where else. I pulled the rear speed sensor and cleaned it, but did not make any difference. I also seems to be better when every thing is turned off such as the heater etc. If anyone has any suggestions please let me know. Thanks in advance.

 

P0483 is Fan speed, Is she running hot around town? Mine has shown that code for a few k miles and everything is fine, here is how i checked:

Check the wiring to fan clutch. Disconnect the wiring harness from the fan clutch assembly.
NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance between the signal circuit in the fan clutch assembly and the return circuit in the fan clutch assembly.
If the resistance less than 10 Ohms,
Replace the fan clutch assembly.

Probably not related to bouncing speedo unless you have an electrical gremelin...