Glow plugs - Peugeot 406TD - captain
Lads/Gals
My Pug 406 TD struggles to start in the morning.My guess is maybe glow plugs but how do i test them
Glow plugs - thomp1983
take them out one at a time, leave the wiring connected then turn the engine onto ignition and they should glow brightly, just be careful not to burn yourself, i usually hold them in a pair of insulated pliers or some such item

chris
Glow plugs - 659FBE
The easiest way to test glow plugs is in-situ with a high current ammeter. An old car type ammeter is ideal as great accuracy is not required, otherwise a conventional meter with a 50A shunt will do. An analogue meter is by far the more suitable. This is because an important part of the test is to observe the reducing current as the ballast resistor in each plug heats up.

Disconnect the wiring and busbar from the plugs (not always easy on an XUD, but you can leave the busbar on the last plug and carefully bend it clear. Apply 12V directly fom the battery via your ammeter to each plug in turn. After an initial current of about 30A, each plug should settle after a few seconds to a running current of 5 to 10A depending on type. Change any plug which fails this test. Take great care to avoid short circuits.

You can check the glowplug controller with a voltmeter on the plug busbar. Note that the plugs stay live after the warning lamp goes out. If the engine is not started, the timer should time out in safety mode after about 20s. For a normal start, there will usually be post-heat for a time dependant upon engine temperature before the plugs switch off.

Change only the faulty plugs, use copper based anti-seize compound on the thread (but not the taper), don't overtighten and above all else, use Beru plugs.

659.