The 1998 Citroen Berlingo runs on diesel fuel and uses glow plugs, which heat the cylinders that cause the fuel and air to explode and power the engine. When the glow plugs break, they must be removed and replaced. The steps for removing a broken glow plug are relatively simple.
Open the bonnet of your 1998 Citreon Berlingo.
Locate the glow plugs. They will be in the centre of the engine. The shape of a glow plug is similar to that of a spark plug.
Remove the connection wire that runs across the glow plugs. Do not bend or mutilate the wire. It must be put back on after you have replaced the glow plugs.
Place the deep socket over the glow plug. Be sure the socket goes all the way to the bottom of the glow plug, to the nut that secures the glow plug in place.
Turn the deep socket counter-clockwise until the glow plug is lose. Do not try to remove the glow plug completely with the socket. Glow plugs are thin enough that they can easily be dropped into the engine compartment and be very difficult to find.
Remove the socket, then turn the glow plug counter-clockwise by hand. Twist slowly and evenly to ensure that you are able to remove the broken glow plug without stripping it.