Depending on production batch. You might get a slightly different reading on you glow plugs. Usually though it will be 1-2 ohms. You are on the lookout for one that has no resitance. It has burnt open. Or burnt out.

This will be the typical failure mode. There are more complex tests if the need is there. Yet if finding the burned plugor plugs and replacing it or them gets you underway is usually good enough.

OK, I just took two hours off work to replace the glow plugs. I replaced plugs 1 to 4. Hopefully that will do the trick. I could see that replacing plug #5 was going to take more time. Have any of you replaced just the first 4?

But why on Earth?

People typically replace glow plugs when they've established they're no longer working.

And you do not need to remove them to test their resistance.

There are dozens of tutorials on the subject.

Or if you'd like to be very thorough.

If the plugs are indeed your issue -and not the relay or anything else for that matter- there's an equal probably that glow plug 5 is your guy.
Are you asking if anyone is content driving around with a malfunctioning glowplug? I think you'll find the answer is no.

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[QUOTE=Are you asking if anyone is content driving around with a malfunctioning glowplug? I think you'll find the answer is no.[/QUOTE]

No that's not what I was asking.

OK, for now the glow plugs are working fine having replaced just plugs 1 to 4. One of these weekends, I'll get to that pesky #5. Now, I wish that I had done it when I had the oil filter housing off of the engine when I was replacing that gasket. How hard have you found it to replace the #5 plug with the oil filter housing in place?

I didn't find it to be hard at all.

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