1998 vw cabrio cranks with a little fire, I have good spark and fuel?

If you're sure you have spark and fuel, AND the camshaft, crankshaft, and distributor are in time, check the engine RPM sensor. The engine will not run with a bad crank sensor. You should see a Tachometer needle rise during cranking, although that's not a hard indication the crank sensor is good.

You should also check the engine ground wires. There are 3 ground wires near the distributor to the left on a bus bar bolted to the block. A cable is attached to the firewall from the valve cover in the back on the left side.

The cam sensor is inside the distributor, so I wouldn't go there unless there was a code for it. The engine will run with a bad or failing can sensor. The cam sensor is used for fuel trim and spark advance settings by the ECM.

If all else fails to get the engine running, get a fuel sample. Disconnect the fuel supply hose from the rail, and fill a clear water bottle with fuel from the fuel tank. Let it sit for about 10 minutes. The sample should be 100% fuel. This time of year, a lot of bad fuel gets pumped into cars from gas stations that are keeping their tanks low. Maybe you should do this first.

coil ?