I bought an 88 samurai a few weeks, drove it home and it ran fine for a while. Offroaded it last weekend and I started having problems. It runs good for 10 or 15 minutes and then sputters out and dies, then it will crank and start and run for a few seconds and sputter out again. It has new plugs, coil and wires, it is getting gas. The thing that worries me is that almost all of the vacuum lines have been plugged. Any ideas?