Recently purchased a 93 Rx7 that had been sitting for 15 years, previous owner cranked it abt 5 years back and said it ran fine and all the gauges worked at that point in time. After purchase, I put a new crate engine in the car. During the swap, I redid the vacuum lines to set the car up for parallel stock turbos instead of the stock sequential, I did not put any resistors in when removing the rats nest, i also had to repair the water temp sensor and the trans speedo sensor bc the plugs broke off while working on the car. Fired the car up and none of the gauges are working. When the key is set to on, the odometer displays a number, but once the car is started the odometer goes blank. I checked all the fuses under the drivers side of the dash, no luck, I checked the ground on the back of the intake manifold and put a ground from the firewall on top of the harness ground just to be sure it was making a good connection, still no luck. I cleaned the ground on top of the gas tank (for the fuel gauge) didn't change anything. Anyone have any suggestions on what to check next? I'm trying not to run the car until I get the gauges working properly so I don't overheat/run the new motor without proper oil pressure.

 

Capacitor plague strikes again. Its a common issue for FD clusters to do this. If you're handy with electronics, there are threads on here explaining how to do the repairs, but if not message Michael Gagne on Facebook as he's the go to guy for repairs. I actually just sent him mine today.