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Discussion Starter #1 (Edited)
Further to the thread I started in on the electrics board, I have checked for chafing damage to the wiring harness and none seems to be present. However, the car is still flashing the ETC light and dropping into limp mode. I've tried clearing the codes and test driving. The furthest I've got without the problem re-occurring is around three miles. As an aside, it's also telling me that #3 glow plug is permanently awol too, although a test shows the plug to be serviceable.

Presumably, if the EGR valve control was intermittent, it would also intermittently cause insufficient recirculation flow? Short of replacing the EGR valve, is there any way that I can eliminate dodgy wiring? Plugging in a resistor, for example.

 

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How did you test the glowplug? A good plug will have a resistance of about 0.5 ohm. If the plug is OK, then maybe the connector or wiring may be the culprit, or possibly the glowplug module. However, a single glowplug failure wouldn't contribute anything to your other problems.
 

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Discussion Starter #3
How did you test the glowplug? A good plug will have a resistance of about 0.5 ohm. If the plug is OK, then maybe the connector or wiring may be the culprit, or possibly the glowplug module. However, a single glowplug failure wouldn't contribute anything to your other problems.
Thanks. I checked for zero voltage drop through the plug while in situ but have since realised that it isn't a particularly reliable test. The only way I thought it could be related is if there was an issue with wiring. To be honest, it isn't my main concern at the moment.
 

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How did you manage to apply the voltmeter probe to the glowplug terminal, with its connector in place? You would also need to take the measurement whilst the glowplugs remained energised - might only be a few seconds after switch-on. In any event, the voltage would not be zero but 4.4V if everything working correctly. The most reliable method is to measure the resistance using an accurate meter with a low resistance scale.
 

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Discussion Starter #5 (Edited)
You considerably overestimate my instestigative skills! I checked the drop though the plug from battery positive to earth. It was only afterward that it dawned on me that it wasn't quite that simple. I'll have another go measuring the resistance when I have a chance. Probably be a couple of days though.

Ignoring the glow plugs for now, I may try unplugging the EGR valve and seeing what happens with a resistor in in its place.
 

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Discussion Starter #6 (Edited)
An update. I disconnected the EGR plug an fitted a 4.7 K Ohm resistor across the end two pins and then cleared the codes. A ten mile test drive of mixed gentle/hard driving was uneventful with the ETC light staying off and the car not going into limp mode. Checked for codes on my return and found a P0401 and the P0673 #3 glow plug warning, both of which I was expecting.

I think I'll drive it for a bit and see if it is happy to run with the resistor and me clearing the code periodically. If not, I'll have to bite the bullet and replace the EGR ££££.

I'll have a look at the glow plug at the weekend and maybe do the resistor trick on the swirl while I am at it.
 
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