1996 Nissan Quest won't start

3.0 liter, 110,000 miles

It almost starts for a second then stops trying even though engine is turning over.
It will run if I spray ether and keep rpms above 2,500 - 3,000 but very thick white smoke comes out exhaust pipe. If I lower the rpm it stalls instantly.

The car sat for four years. Oil pan and rear valve cover were missing. I gave it to a repair shop and they put on the parts but left off the PCV hose, colapsed the bottom EGRC-BPT valve vacuum hose and installed the distributer and notch off.

The engine was easy to start and would run (although, not real well). I fixed the above, put in new plugs and plug wires (#1 was arcing). Started car and it ran great for about 30 seconds, check engine light came on but it still ran great for another 15 seconds.
Shut it off and started it a few minutes later. Ran great for another 30 seconds then it just shut off. Would not start again.

There is 3/4 tank of gas and I don't think the shop put it in so they must not have changed it. I'm going to drain the tank next. The fuel filter tested OK.

One other thing I don't understand:
Compression on back three cylinders (1, 3 and 5) is 210 psi and the front three (2, 4 and 6) are 145 psi.

I would really appreciate any advice.