I had a 92 Chevy Lumina checked their.well ask them if they have a codes reader for rent. they some times rent them. you get all your money back when you return the tool. if not see if they have one for sale that will fit the van. I think the one I bought was about $40. try talking to some one different at auto zone. some of the people are just learning. and some really know their stuff.
how is the temp gage? or does it have the dummy light?
if you do get a codes reader. plug it in. you should get code 12 three times.this lets you know the computer is talking. then it will flash the other codes three times each.