Checking glow plugs (VW Transporter T3)

Remove the supply wires and glow plug bus.

Connect the test light to the positive terminal of the battery and touch it to each spark plug in turn.

If the light bulb lights up, the spark plug is good.

If the bulb does not light, the spark plug is faulty and needs to be replaced (tightening torque 30 Nm).

Current consumption of one spark plug is about 12 A. With the total consumption of all spark plugs about:

• 36 A - one spark plug is faulty;
• 24 A - two spark plugs are faulty;
• 12 A - three spark plugs are faulty;
• 0 A - all spark plugs are faulty.

These current values are only achieved when the battery voltage is above 11.5 volts.

Candles with burnt-out glow rods.



Burnt spark plug rods are often the result of faulty injectors. Such damage is not caused by faults in the spark plugs or their circuits.

(28-251) If you find spark plugs like those shown in the picture, it is not enough to simply replace them. You also need to have the injectors checked in the workshop.