Engine Mechanical problem
1986 Nissan 300ZX 6 cyl Two Wheel Drive Manual 204000 miles

I bought my 86' 300zx N/A just recently not running*. I was told that the vechical was running fine, untill the previous owner replaced the spark plugs and wires. Now the car will start for 2sec. and die. seems like its runninig out of fuel. will stay running on starter fluid. I've checked the following: spark plugs, firing order, all electrical connections, new battery, fuseable links, fuses, fuel pressure(39 psi), fuel pressure regulator, fuel filter, coil packs, all vaccum lines, fuel pump run's fine on initial turn of key to the on postion. will not stay running. Have to take key out for one minute before it runs again. I've been working on cars for years now and have never been stumped like this before. Can you please Help me? Thank you in advanced. Shawn