A spare sparkplug will serve that purpose without having to remove one from the engine.

Listen for the pumps to do a short cycle run when you first turn the key to "on". The most common (IMO)source of a no start in the b230 cars is the fuel injection relay which is located on the inside firewall above the passenger's feet. Remove the knee bolster and you will see it clipped to the firewall. If the pumps are not cycling they are not running when you attempt to start it (although the relay can be intermittent). If you solder you can simply reflow the joints on the board.

There is also the 25amp fuse in a holder on the driver's inner fender. It can corrode and lose contact with the holder. Pull it out and clean it up or replace with a marine grade holder and never worry about it again. Follow the red wire from the positive battery post to find the fuse holder. Clean the connection of this red wire to the battery as well.

Randy