Speedometer Bouncing (Fixed)

[Junk Basket]

So a couple of months ago my TJ speedometer just started bouncing around. Hoped it was something quick and easy to fix. Didn't have time to fix myself ( July 4th Vacation)so took it to the shop, they slapped in a new gear and sensor and told me she was good to go. Well it wasn't...

I can't find the thread I read, but a couple of others changed the spark plugs and wham speedometer worked again. Before taking my TJ back to the shop in anger. I figured why not change the plugs since they where due for a change. Sure enough speedometer is back to working a 100%. I figured I would post as a note for someone else struggling with the same issue.

 

[Jablinski]

So a couple of months ago my TJ speedometer just started bouncing around. Hoped it was something quick and easy to fix. Didn't have time to fix myself ( July 4th Vacation)so took it to the shop, they slapped in a new gear and sensor and told me she was good to go. Well it wasn't...

I can't find the thread I read, but a couple of others changed the spark plugs and wham speedometer worked again. Before taking my TJ back to the shop in anger. I figured why not change the plugs since they where due for a change. Sure enough speedometer is back to working a 100%. I figured I would post as a note for someone else struggling with the same issue.

This is definitely an oddball solution. Glad it worked for you but what do spark plugs have to do with VSS? I think a ground for the PCM is relatively close to the distributor (Edit: on my 98. I see you have an 06) Maybe moving that around while changing plugs/wires gave it better contact?

 

[SWO1972]

This is definitely an oddball solution. Glad it worked for you but what do spark plugs have to do with VSS? I think a ground for the PCM is relatively close to the distributor (Edit: on my 98. I see you have an 06) Maybe moving that around while changing plugs/wires gave it better contact?

The 06 ground is on the passenger side of the engine, near the distributor looking thing. My speedometer is doing the same thing so i changed the sensor and gear, but no luck. I'll try the cleaning the ground next, although it looks fairly clean, and then as a last resort, I'll change the plugs.