I've been reviving my 81ZX that has sat for several years & am making progress. My fuel pump was frozen so it was pulled, disassembled, & cleaned. The fuel filter was plugged & couldn't blow air through it, replaced. Replaced several old fuel lines at the fuel tank & filter area and have good fuel pressure now. The injectors were frozen so put Marvel Mystery Oil in the fuel rail, pressurized, hot wired each injector while heating with the heat gun. I suspect I need to run some fuel with detergent through the system before all will run smoothly. Next I had a spark problem. Checked my notes and had never replaced the plug wires which were reading about 15k ohms, replaced. Started running ok but not smooth. Then I started having loud ticking noise. This has happened several times and each time it has been a lash pad being thrown off the valve probably a sticking valve situation. I've got Marvel Mystery Oil in the oil now hoping this will soon stop. The last incident was a loss of manifold vacuum, down from 19 to about 10"Hg at idle. This was a lash pad that rotated 90 degrees and was holding the #2 intake valve open. Found it when I was checking all of the valve lash. I adjusted the valve lash on four valves while I was at it and the last run was pretty smooth. Now I think I just need some miles to work the detergent through the fuel and oil systems. Over the years I've had some connector problems under the hood. At present, all of the connectors on the fuel injectors & cold start valve, & head temperature, have been cut off and soldered on. This has helped allot for reliability.