Speedometer/transmission/please help!

I have a 2001 Chrysler Voyager and a few days ago, the speedometer needle suddenly started jumping all over while my car was at a full stop. It’s fine while in park, and it’s only when I have the breaks on at a full stop–I can decelerate just fine, and everything seems to work as soon as the car is moving. While it is at a complete stop, my van also occasionally jumps as if it’s trying to shift into gear and move itself. This all started on Thursday when the temperature suddenly dropped. Any ideas as to what might be wrong with it and how much it will cost to fix???

Is the check engine light on?

Strange symptoms but I would first perhaps suspect an issue with the vehicle speed sensor and or its circuitry.

That’s just a shot in the dark but no one had responded yet so at least your question gets a “bump”.

I’m geussing a bad sensor. Rather a nearly bad sensor. Chrysler has a set of sensors for the engine speed, the transmission speed and the axle speed. The sensors are about 60 each but you need a trusty mechanic to find the right one. My guess is the output sensor to the differential. Just did one on my 95 cirrus. The cost should be about 120. It is not to hard to get to but the sensor is about 60.

It sounds like you have an issue with the output speed sensor. These transmissions are known for their speed sensor issues. Scan the computer for codes, you will probably see and output speed sensor code along with one or more gear ratio codes. Post back with the code/s and we can go from there. Most likely you will be replacing both the input (Turbine) speed sensor and the output speed sensor. These can be purchased for less than $50 and are easily installed.


How do I scan for codes?

Take it to one of your local auto parts stores, most will read the codes for free. Have them check for current codes and history codes. Write down the code numbers and descriptions and post them back here and we can go from there. More than likely you will probably get an output speed sensor code along with one or more gear ratio codes. While you are there, price an input (Turbine) speed sensor, and an output speed sensor. This is a very common problem in these transmissions. I see it very often. Post back as soon as you can.