This speedometer problem is killing me!! HELP!!!

[gjack]

Hello everyone! I hope there is someone out here that can provide a little Holiday magic. I have been trying to work this problem out for several weeks now.

It's my son's 95 Talon ESI. This problem has existed since we bought the car.

Periodically (90% of the time) the speedometer starts to rise slowly when the ignition key is turn to the on position. When you start the car it shows 20-60 mph then slowly falls back to normal. While you are driving it is fine about 98% of the time (once it’s back to the normal position) but sometimes it will start to slowly rise and peg the needle and go back to normal.

We just put in a new remanufactured transmission with all new sensors.

I have cleaned every chassis ground a can find.

I have replaced/returned all the hacked up wiring from a poorly installed radio back to factory.

Checked all the connections at computer in console, many connections under hood including cam shaft, crank shaft, input and output speed sensor.

Pulled and clean instrument cluster connection.

Could this be a cluster or PMU problem?

Happy Holidays!

Jerry

 

[ADrewzki]

Jerry,
Definitely sounds like a dsm! First thing I would try is a different cluster. They're relatively cheap to get from a junkyard or from people parting out their cars. I believe I got mine for $45 for everything. If that still doesn't work and you are sure that the speed sensor is good, I would start looking at the ECU. Problems like this are usually pretty tough to find. Good luck and keep us updated. -Drew

 

[gjack]

Thanks Drew, any help/wisdom is greatly appreciated. I have been leaning towards the ECU but maybe I’ll try out a cluster first. I was hoping some one had experienced the same problem.

Jerry

 

[gjack]

It looks like the problem was the connector just before the starter. While my son was watching the speedometer I started checking all the connectors again, as soon as I touched that particular one the speedometer drop right to zero and hasn't raised sinse. Go figure!!

This has been a real pain in the @$$ but I’m glad it’s finally working correctly and I hope this helps someone else who has already changed the trans sensors and still has a problem.

Good luck and thanks again Drew!

Jerry

 

[boostcreep]

How did you check your speed sensor I popped a code for the speed sensor. Any special tools?