1990 lumina apv van trouble

I have a 1990 Lumina apv van, I bought it the guy told me it had a bad fuel pump but I bought it because it had a nice body on it, I put new battery in it, tried starting it, it would not start no matter what, I just thought I would try it because the battery was dead. then I took the air cleaner off then it started up. When I took the air cleaner off I unhooked the map sensor. It runs without the map sensor hooked up. When I pluged the map sensor back in it stalls and wont run. It runs fine with it unhooked but the engine light is on. how hot does it have to run before the electirc fan comes on?
I looked by the distributor and oil is comming out, where the distributor meets the block its comming out pretty good. do you think its the fuel pump or map sensor? Is there any way to test the map sensor?

I have a 1990 Lumina apv van, I bought it the guy told me it had a bad fuel pump but I bought it because it had a nice body on it, I put new battery in it, tried starting it, it would not start no matter what, I just thought I would try it because the battery was dead. then I took the air cleaner off then it started up. When I took the air cleaner off I unhooked the map sensor. It runs without the map sensor hooked up. When I pluged the map sensor back in it stalls and wont run. It runs fine with it unhooked but the engine light is on. how hot does it have to run before the electirc fan comes on?
I looked by the distributor and oil is comming out, where the distributor meets the block its comming out pretty good. do you think its the fuel pump or map sensor? Is there any way to test the map sensor?

Map sensors are cheap. Just put one on it. The distributor probably just needs a new o-ring, or the clamp isn't tight. The fan should kick in sometime before the idle temp goes into the hot zone, it varies from car to car. They should run whenever the A/C is turned on IF the compressor is engaged. If the system is low, the comp won't cycle, and the fans won't run.

Thanks did everything you said and it now starts and stays running. so I guess I got lucky

need to find out how many freeze plugs that are on the engine of my 1990 Lumina APV van i believ there are two. is there any way of replacing them without pulling the engine there is one on the front and back and they have popped out