Morning all!
After work yesterday my red flashing light in the temp gauge flashed when the ign is turned as normal and went out. However a minute after firing up the light was back.
I drove home up a couple of big hills and the Temp gauge stayed rock steady and perfectly normal. and oil pressure is fine on the gauge.
Ive always assumed the light to be a high temp warning light, but it occured to me it might be low water level?
What is its function? and any thoughts, my feeling is the sender , or the connector has fallen off an is earthing out on the eninge. will have a loojk this weekend!
Also Glow Plugs have been progressively more intermittent of late, sometimes when parked on an angle they work better, and sometimes by working the key they might work but the led often flutters out quite quickly.
I think its either the relay in the black box in the engine bay or the ign switch - are both common culprits?
Did do a search on the glowplugs but couldnt find much, not been a problem over summer but any miute now ill have starting issues!
Couple of issues.....thoughts please!
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- fodtommo
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Couple of issues.....thoughts please!
1986 Leisurdrive Poptop, 1.6d - Rebuilt and Camping with a Vengeance 

- Mickyfin
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Re: Couple of issues.....thoughts please!
The coolant light take its readings from the water level in the header tank, and, high water temp reading from the sensor on the radiator afaik.
Owner of Flintstone, our T3/25 Caravelle C Syncro 1.9 Petrol.
- fodtommo
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Re: Couple of issues.....thoughts please!
Ahh thanks - ive never bothered finding out what the light means (slack i know), but now Iknow it does both, it must be coolant level if anything as the temp gauge is normal and it starts before the engine is warm!
1986 Leisurdrive Poptop, 1.6d - Rebuilt and Camping with a Vengeance 

- ewenmaclean
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Re: Couple of issues.....thoughts please!
Hello
the temperature gauge takes its input from the coolant flange in the engine bay and the header tank. If the level is low then this is controlled by module 43 in the fuse box, and causes the light to come on. The radiator sensor is purely for the fan to come on - it has nothing to do with the gauge. Have a read on the wiki here:
https://club8090.co.uk/wiki/Co ... ht_on_dash" onclick="window.open(this.href);return false;
It sounds like you have a grounding problem with the glow plugs somewhere - if you're only judging whether they come on via the glow plug light, I would ignore that and actually test with a multimeter whether they are working - there's a good chance it's just a dodgy earth at the glow plug relay for the glow plug light. If not then yes the ignition switch is a possibility as is the relay itself, but first off I'd check continuity to earth and clean up the connections for the glow plug relay, and actually check whether the glow plugs are coming on or not.
Ewen
the temperature gauge takes its input from the coolant flange in the engine bay and the header tank. If the level is low then this is controlled by module 43 in the fuse box, and causes the light to come on. The radiator sensor is purely for the fan to come on - it has nothing to do with the gauge. Have a read on the wiki here:
https://club8090.co.uk/wiki/Co ... ht_on_dash" onclick="window.open(this.href);return false;
It sounds like you have a grounding problem with the glow plugs somewhere - if you're only judging whether they come on via the glow plug light, I would ignore that and actually test with a multimeter whether they are working - there's a good chance it's just a dodgy earth at the glow plug relay for the glow plug light. If not then yes the ignition switch is a possibility as is the relay itself, but first off I'd check continuity to earth and clean up the connections for the glow plug relay, and actually check whether the glow plugs are coming on or not.
Ewen
- fodtommo
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Re: Couple of issues.....thoughts please!
Thanks Ewen - the plugs are not working when the light is off as A) it dosnt as well and the ubiquitous puff of smoke is much greater and B) with the lights on at night they dont dim as the normally do if you have the plugs on.
I will get the multimeter out and get fault tracing this wweekend!
I will get the multimeter out and get fault tracing this wweekend!
1986 Leisurdrive Poptop, 1.6d - Rebuilt and Camping with a Vengeance 

- ewenmaclean
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Re: Couple of issues.....thoughts please!
Hello,
ok - thanks for clearing that up. I would suspect in which case either a faulty relay (I've got a spare one you can have to test if I can find it in the loft), or the ignition feed itself. That could be, as you say ignition switch related, or a dirty connection in the engine bay.
Let me know if you want the relay to test and I'll try and find it later
Ewen
ok - thanks for clearing that up. I would suspect in which case either a faulty relay (I've got a spare one you can have to test if I can find it in the loft), or the ignition feed itself. That could be, as you say ignition switch related, or a dirty connection in the engine bay.
Let me know if you want the relay to test and I'll try and find it later
Ewen