[msg123456]

Hi all,

Just wondered if anyone has experienced this.

I have a 2004 sebring with automatic transmission.(not sure what type) but when I am at a stop with the transmission in Drive, sometimes the speedometer will speed up to around 20kmh and then drop down again, even though I am stopped.

msg

 

[ImperialCrown]

I would take a close look at the 41TE transaxle output speed sensor and connector. A poor connection or the sensor itself may be 'tickling' the speed signal output wire with a voltage and creating a false speed signal.
The signal goes to the TCM where it is then bussed out to the other modules including the instrument cluster.

 

[msg123456]

Thanks Imperial, do you know where the sensor is located?

 

[chuzz]

Usually on top of the transmission near where the transmission lines are. I think!

 

[ImperialCrown]

That would be in the front (radiator side) towards the driver's side under the shift cable crank and shift rod.
It is a 2-wire sensor and a 1" or 1 1/16" socket should fit the sensor.
There may also be a build-up of iron filing 'mud' at the magnetic tip that can skew speed readings.

 

[msg123456]

Thanks very much chuzz and Imperial,,will check that when I get a chance and let you know how I make out.

 

[chuzz]

If you go to replace it, just be careful with the new one. They're made of some type of plastic and you don't want to over torque it. Just snug it in.

 

[msg123456]

Thanks again chuzz.

 

[msg123456]

Looks like there is a input speed sensor also, wondered if I should change this one too while I am at it? if they are not too expensive..

 

[msg123456]

Hi , I have an update on my problem...The surge I am speaking about only seems to happen when the air conditioning is turned on. Could it still be related to the input sensor or should I take it to the dealer to see if there is a recall on this problem?

Thanks..Max

 

[ImperialCrown]

I can't see the Input Speed Sensor causing this problem as it has nothing to do with the speedometer or A/C. There are no recalls or TSB's for what you describe.
Is it doing this consistently in wet or dry weather? Does the engine speed vary more than normal as the A/C compressor cycles on and off at an idle?
Did you look at or replace the Output Speed Sensor? That is the one that controls the speedometer.

 

[msg123456]

Hi Imperial, unfortunately I will not have time to do this on my own because I am going on a long trip this week..Have to take it to a shop but will let you know what they say..Appreciate all your help though..

 

[msg123456]

Hi again, took it in and they could not find anything so will look at that sensor after my trip..will let you know how I make out.

 

[msg123456]

HI all, well the alternator failed of course on my vacation but I managed to find a good mechanic to fix it..Turned out, once the alternator was changed, the surging problem has gone away also.

 

[chuzz]

Thanks for posting back and letting us know. I had an uncle years ago that told me if I was going to drive Mopars, I should carry a pocket full of alligator clips and wire in the glove box because they have strange electrical problems from time to time. He wasn't a "mechanic" by trade, but sure spent a lot of time under the hoods of his old cars. And not all of them were Mopars, either!