Glow-plug/Pressure sensors

[Spineytoo]

I had the "Service vehicle soon" message on the display. I measured the resistances of the four glowplug/pressure sensors (Between the centre connection and a convenient metal part of the engine.). Two were around 1.2 ohms, one read 3.6 ohms and one was open-circuit. I was horrified to find the asking price of the combined glowplug and pressure sensor was £120. I found a new OEM one on Ebay for £88.99.  I replaced the open-circuit one and still got the "Service Vehicle soon" message.  Not having a diagnostic tool, I could not verify if it was the glow or the pressure sensor or, indeed, anything else causing the warning. I bought another glowplug/pressure sensor and fitted it. After one more warning, the message disappeared. Job done.  You do need a multimeter capable of giving reliable, accurate low-resistance measurements.  I used "Copperslip" on the thread before screwing the new plugs in.

I bought a 1/4" square-drive torque wrench on Ebay for £15.40.  The settings were difficult to read and the markings on the rotating handle did not match the engravings on the barrel, making it very difficult to have any confidence at all of the actual setting. It is very dangerous to exert much more than 10 Newton metres torque either for removing or tightening down, as the top of the plug can be turned off leaving most still stuck in the cylinder. I was lucky, both mine unscrewed easily. (If you break one, think about ignoring it and relying on the other 3 plugs!  Use penetrating oil and run the engine hot before attempting removal.)

Another tip; the electrical connectors just pull off but are very stiff. Use a long thin screwdriver at the bottom of the plastic connector cover, twist and the connector pops up a few mm.

[Vauxhall Owners Club]

Thank you for posting up this very useful guide on replacing the glow plugs.

I have a feeling (going by the fact that there is a lot of mention of it being a very cold winter this year) that there will be a lot of glow plug replacements being done this year