91 RS, non-cable drive unit. Sometimes it works, most of the time it doesn't. Weather has no effect. Odometer works when speedo does. Cruise works regardless.

200k miles..showing..closer to 215k

 

If cruise works regardless, than the tranny sending unit is good,
and the problem can probably be isolated to the speedo head
in the gauge cluster. Go troll the parts for sale section -- there's
usually gauge cluster available. If not, start a post in the "Want to
Buy" section.

I just hooked up with a cluster for my firebird -- speedo
& gas gauge problems.

 

Sometimes the bolt that holds the speedo cable into the trans case works loose. Jack her up and double check, should be near tailshaft area. I would start there.

 

Note that the OP's car isn't cable driven.

JamesC

 

Sender or cable same diffrence, its the bolt that goes into the plate that holds the speedo gear into the tailshaft, I would check that its tight before anything else. I used locktite on mine after the third time it came loose.

Edit, I just caught that it was a T5, but it should be the same concept, just not sure where exactly the sender is located on the trans, correct me if im wrong. I did catch the part about cruise working, I was just saying to double check your speedo gears bolt before buying parts/tearing dash apart, as its so easy to check.

 

The VSS is located in the same place.

Agreed. Try the simplest fix first.

Gary/Pam, the electronic speeo issue is somewhat common to our cars. You might consider a search as the problem has been discussed many times before. Best of luck with your project.

JamesC