My 1992 Honda civic revs backward /reversely. Please can anyone help me the solution out to this problem.
2. Where is the ECU of my car located?

 

If the needle ever goes below zero, that would be a problem with the tach head itself. They have capacitors in them which are likely bad after 25 years.

The ECU is located on the side of the car under the carpet just forward of the passenger's door.

 

Thanks for the response.
How do I remove and repair/replace the tach?