Glow plug relay click

[Nvm]

Hi all

I've just replaced my glow plugs and relay switch, but now I don't hear the 'click' after the glow plug light goes out. What could be wrong now?

[Northern Bongolow]

put a test lamp to the head of the glow plug and to earth, just to see if the plugs are getting 12volts, then take it from there.

[Nvm]

I'll check that or at least ask my local garage to, TA.

[francophile1947]

As the glow plugs are still working after the light goes out, should there be a click until the plugs are no longer powered

[teenmal]

Hi all

I've just replaced my glow plugs and relay switch, but now I don't hear the 'click' after the glow plug light goes out. What could be wrong now?

Possibly nothing, the relay wont dropout (click ) until the engine has reached the predetermined temperature which could be several minutes after the light goes out.


PS are you talking about not starting the engine.

[Nvm]

Thanks for the replies so far.
In the past when I half turned the key the dashboard lights came on including the glow plug light. Then the glow plug light would go off after 5 to 10 seconds ( the engine not started) there would be a click several seconds after the glow plug light goes out. At which point I would turn the key full to start the engine. When I do this now there is no click.

[mikeonb4c]

Thanks for the replies so far.
In the past when I half turned the key the dashboard lights came on including the glow plug light. Then the glow plug light would go off after 5 to 10 seconds ( the engine not started) there would be a click several seconds after the glow plug light goes out. At which point I would turn the key full to start the engine. When I do this now there is no click.

Mine behaves like yours used to. Maybe the replacement is an improved click-free design? Maybe if the car is starting and behaving fine, then why worry? But it does seem a bit odd, and worth asking about on here

[Nvm]

Ok I have it on good authority that the click you hear after the glow plug light goes out on the half key turn indicates that the switch is in fact faulty! Not so much faulty but not working how it should. NOT hearing a click is how it should be. Now I don't know what but. SHOULD THE BONGO CLICK OR NOT CLICK?

[rita]

Ok I have it on good authority that the click you hear after the glow plug light goes out on the half key turn indicates that the switch is in fact faulty! Not so much faulty but not working how it should. NOT hearing a click is how it should be. Now I don't know what but. SHOULD THE BONGO CLICK OR NOT CLICK?

If the ignition is switched on the relay should drop out approx 10 seconds after the light goes out.

If you start the engine the relay will stay energised until the engine is up to temperature. As has been said check the voltage on the glow plug (heater) rail that will let you know what is happening.

[clutha]

I was about to check out my glow pugs as I also had the lumpy tickover and smoke on a cold start.
Some improvement occurred when I gave the plugs two cycles in cold weather.,something I remembered being advised to do when I had a Citroen diesel.
Having studied most of the posts on here now, I'm waiting until about 10 secs after the glow plug light goes out.
The difference has been dramatic. Immediate smooth idle and no smoke.
I'm noticing I get no 'click' when the engine is cold, but I do on a warm start.
Can I assume this is because this temperature cut out needs to see an elevated engine temperature and a cold engine needs more time to reach that temp.

[Tony x]

The power to the glow plug rail can stay on for 5 minutes or so when starting from cold.
When starting from warm, the power can go off very quickly.
At times, usually in cold weather, the power may go off after a few minutes and then come back on for a couple more minutes
In warm weather, it may go off quicker but again come on again briefly.

I know this as a little green LED on the dash indicates when power is going to the rail

[clutha]

The power to the glow plug rail can stay on for 5 minutes or so when starting from cold.
When starting from warm, the power can go off very quickly.
At times, usually in cold weather, the power may go off after a few minutes and then come back on for a couple more minutes
In warm weather, it may go off quicker but again come on again briefly.

I know this as a little green LED on the dash indicates when power is going to the rail

Is your little green led a mod?

Using the van in runabout mode today.
1. First start from cold, dash glow plug light out, waited 10 secs, perfect smooth revs after start.
2. Next start after 2 hour stop, absolutely fine, ( gave it 10 secs again after light out )
3. Next start on warm engine, light went out very quickly followed immediately by loud click.
Start was fine and smooth revs.

I'm of the opinion most people think when a glow plug light goes out its ok to start a diesel engine.
Our VW powered Seat starts fine this way, as did our Citroens and Peugeots.

Anyway, great advice on here, saved me hassle of checking out plugs.
Thanks.

[Simon Jones]

I'm of the opinion most people think when a glow plug light goes out its ok to start a diesel engine

That is how it's supposed to be when everything is working correctly . This is from my Volvo manual: