Faulty glow plugs?

[phibbzy]

I have gathered up the entirety of my glow plug collection - amount to about 18 for the 300tdi.

Using a multimeter set to 20k resistance (from memory) I get a reading of around 0.06 to 0.10 on around 5 of them, the majority of the others flicker a reading for a second then show open circuit and the rest don't change the meter at all.

Using a 12v car battery, earthing the body of the plug and positive on the top though, none of the glow plugs generate any heat or draw any current at all...

Am I testing them wrong or area they all buggered?

[phibbzy]

Turns out I have 18 faulty glow plugs 8 from 2 running vehicles and another 4 taken from an engine removed from a running vehicle with a head gasket failure.

I would have thought at least those should have had a good win/lose rate! I will be checking my plugs more often now I think...

[CraigE]

Thats a huge failure rate. Have you had someone else test them to be sure?

[phibbzy]

Thats a huge failure rate. Have you had someone else test them to be sure?

2 others! They've been tested many times with various methods.

[3lud13]

2 others! They've been tested many times with various methods.

Out of curiosity and since my glow plugs are currently out of the vehicle how does one go about testing them

[phibbzy]

Out of curiosity and since my glow plugs are currently out of the vehicle how does one go about testing them

Easiest way is to run a healthy 12v current through them, positive on the top and ground it to the body (the thread).

You can also use a multimeter to test the resistance through the plug.