I have a 1991 Trans Am GTA and I'm having random speedometer issues where it'll just stop working. I've already changed the Vehicle Speed Sensor and that didn't solve the issue. I already know it's not an instrument cluster issue because when the speedometer stops working, so does the cruise control. What else should I check? A possible short in the VSS wire?

When I say random problems, it's like REALLY random. For example: one day the speedometer wouldn't work at all and then not a single issue the next day. Today, it started off not working and then it did later then stopped again.

 

When you replaced the VSS, did you inspect the gear on the output shaft to see if the teeth on it were still good?

 

It is probably the electronic resistor leaking in the electronic circuit board that controls.

This happened in my 92 z28

 

I hate when resistors take a leak on circuit boards.

 

The transmission was fully rebuilt a few weeks ago. I ASSUME all of that was taken care of.

 

Where would that resistor be located?

 

Is the check engine light coming on and ecm storing a code 24 ?
tpi ?

 

The Check Engine Light has been rendered obsolete because my car's power train is managed with the Holley HP EFI ECU. For the record, I was having this speedometer issue when my car was bone stock.

 

Does the Holley get a Vss signal you can watch or datalog ?
do you have a Vss buffer ? Cable drive speedometer ? Dakota digital sgi5 or 100bt ?