First I have searched for this. I have just replaced the fuel sending unit with a new one from Mazdatriz and I get no reading on the gage. I unplugged the fuel sending unit and jumped the wire and got no movement from the gage with ignition on. Have checked meter fuse and its OK. Any thing else I can check? I am stumped. 81 base model.

 

Pull the dash cluster and check the gauge itself. On the back of it there is a bar with fine white wires wound around it. If there is any discoloration of those wires, blackening or browning, the guage is toast.

 

Does the plug have any corrosion on it? If so, try cleaning it up a bit. Otherwise, it sounds like its the gauge as trochoid said.

 

If the gage is toast do I have to replace the complete system (fuel, tach, speedometer etc)?

 

Nope, just the dual gauge on that side.

 

I am having a similar problem with my newly purchased 82 model. I will be doing some troubleshooting to verify that it is, in fact, the gage that is the problem. That said, do you know where the best place is to purchase a fuel gage? Online? Auto parts store? Junk Yard? Any help would be great. Links to sites would be awesome. Thanks.