My fuel gauge will not move all the way to full. This gauge has been in this condition since purchasing the Z. Where should I start to diagnose the problem?

It could be the Gauge itself or more likely the sender unit in the tank also. The sending units are still available OEM and I would start there. A whole lot easier than replacing a Gauge.:classic: My opinion only. John

Edited January 16, 201015 yr by barth4567

It could be the Gauge itself or more likely the sender unit in the tank also. The sending units are still available OEM and I would start there. A whole lot easier than replacing a Gauge.:classic: My opinion only. John

I just went through this exact issue on my '78.

It just may be the gauge. Does your ampmeter seem to work correctly?

I was looking at replacing the fuel sending unit as I hear they do go bad and since good working voltmeter (or ampmeter depending on the model)/fuel gauges seem to be hard to come by these days. So I just put my dash back in with the old gauge and figured I'd have to live with it.

I have noticed that the voltmeter did not seem to working correctly for some time. Then after putting the dash back in, I found a properly working voltmeter/fuel gauge.

The good news is that I was able to swap it out easily. It's nowhere near as hard to do as I thought it would be. Even better, the fuel gauge now moves all the way to full and the voltmeter reads correctly! The whole job took a little under 30 minutes.

So, I would question whether swapping the fuel sending unit is either easier or cheaper than replacing the gauge.