Removing
1. Disconnect the ground cable from the battery.
Attention! If the car radio in your car is coded, make sure you know the code before disconnecting the battery.
2. When working on the F9Q engine, remove the plastic cover from the right engine support, then disconnect the high pressure fuel lines from the fuel pump and injectors as described in Chapter Power and exhaust systems.
3. Remove nuts from glow plug terminals and remove washers. Disconnect the wiring (refer to accompanying illustration). Please note that the main power wire is connected to two candles.
4. Gently move the tubes or wires to the side to improve access to the glow plugs.
5a. Loosen the glow plugs.
5b. Remove them from the cylinder head (refer to illustrations).
Inspection
1. Inspect each glow plug for physical damage. Burnout or rupture of the glow plug tip can be caused by poor atomization of fuel by the injector. Check the injectors if you find this type of damage.
2. If the glow plugs are in good physical condition, check them as described in the previous Section.
3. Glow plugs can be powered by applying 12V to them. Observe the following precautions when handling candles.
- a) Hold the glow plug in a vise or self-locking pliers. Be aware that it gets very hot.
- b) The power supply or test lead must contain a fuse or overload indicator to protect against short circuits.
- With) After checking the function, allow the glow plug to cool down.
4. The tip of a glow plug in good condition glows red hot for 5 seconds. If the spark plug glows more slowly, or if the center glows rather than the tip, it must be replaced.
Installation
1. Install in reverse order. Apply a small amount of copper anti-seize compound to the spark plug threads and tighten the glow plugs to specification. Do not overtighten as this may damage the heating element of the spark plug.