speedometer going haywire

[Slowsupratt]

I'm in the tale end of of pulling out my aftermarket sound system and putting in the stock one.

Now, when I turn on the car and let it idle the speedometer bounces all around and the odometer starts moving as if i was driving.

I have no clue what to check to see what could be causing this so any ideas are appreciated.

 

[KNG SNKE]

sounds like you hooked the wrong wire into the speed sense wire or grounded it somewhere or it is grounding through your radio. All speculations, need more info.

 

[bluesrt]

reverse procedure/ unhook the stereo/ what ever you had your hands on, see if that stops the crazyness

 

[Venomiss]

What exactly did you install? Surely someone has an idea for you to check.

Maybe consider joining the VCA since you have been around a while?

 

[cfiiman]

I by no means am a Viper expert, but a while back I started my 94 and the rpm gauge dropped to zero then bounced back up then repeated the process several times and then leveled out, hasn't happened since (probably 15 drives since then maybe more). Anyway the reason I mention this is I was given the advice it could be the battery as these cars act really funny when voltage drops, maybe hooking up the stereo has showed a weakness in the battery, just an idea

 

[dave6666]

sounds like you hooked the wrong wire into the speed sense wire or grounded it somewhere or it is grounding through your radio. All speculations, need more info.

This. The factory radio uses a wire from the speedo (or PCM) to adjust volume up or down when you are driving. Make sure that wire is not connected to anything with your new install.