When I put freon in ac motor runs for 1 to 2 seconds
what tumbleweed said you wouldnt be able to add r134a if it hadnt been converted
The connections for R-12 and R-134a are different so if your A/C equipment was able to connect it's R-134a fittings to the car then I would say that someone has already changed the car over. On my car I changed the fittings, added new compressor oil and then had it vacuumed out before adding the new R-134a. It works marginal but I don't think you can ever get them to work as good as the R12 did.
Wrong freon. Old system is probably full of air and cannot accept any freon, compressor bad and leaking etc. If you take it to an a/c mechanic he can change it to the new system. Big bucks though.
To properly change it over, you need a new compressor and dryer. As mentioned, you could take it to a place that does A/C and ask them about it.