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I don't always see the glow plug symbol on the dashboard display ? watch

    • Thread Starter

    I very rarely see the glow plug light when I turn my car ignition on, does that mean it needs replacing ?
    I have a few problems with my car as well which I guess a fault in the glow plug relay could create.

    Very rarely I see it on the dashboard but it does come on sometimes

    any ideas?


    As far as I'm aware they'll only come on when they're needed, when the engine is at a low temperature, can't say I'd know what the temperature is but they won't always come on, even during the winter. I suppose it wouldn't hurt to get it checked out by a trusted mechanic just in case.

    Why are you so obsessed with the glow plugs? They barely do anything, you could disconnect them completely and the only thing you'd notice was slightly longer to crank and a bigger puff of black smoke - but only on cold mornings. On any morning over 5ºc and it'd start as normal. When the light doesn't come on it's just the ECU ascertaining that they aren't necessary and simply not using them. I never used them on my old car and haven't yet used them on my current one, and both fire/d up the moment you turn the key.

    A lot of modern cars energise the glow plugs (if they're necessary) when the door handle is opened, but it's quite likely the symbol won't appear until the ignition is turned on. If the thing is starting ok, don't worry about it...
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