Weird Idle, cutt off, missing problem 1990 Troopoer V6

Ok, I changed the plugs, wires, distributor and all vacuum hoses/connections. After warm-up, the engine revs itself up to 4000 rpms or higher for a few seconds then cuts off completely. While driving it'll just shut off intermittently as if someone is turning the key off (but that is not the case). Anyone have any ideas?