Hi guys, having Engine managment light coming on and off every few times i start car, been to garage and they checked it and code shows "undocumented error", anyway its come down to the glowplugs or relay. WHen i start the car usaly its fires up no problmes (though does sound rough as it always has done), sometimes i get it little puff of smoke on cold morings. Anyway today iv done a resistance test and for the 4 plugs, 3 are showing 0.25 ohm and 1 is showing 0.44 ohm. Does this mean there ok? any help would be welcome. Thanks.
glowplug resistance, inc loss of steering- New battery?
- Thread starter rabu
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Typically a glowplug resistance will be around 1 to 2 ohms, and with resistances as low as this I think its quite difficult to measure them accurately (corrosion on terminals, pressure of crocodile clip etc).
I've found that they either go open circuit (no resistance) or they work!
Yours sound OK to me, and I think its a good move to time the heating interval next.
Its acceptable to unscrew a plug from the cylinder head and watch it glow, if you like.
John
I've found that they either go open circuit (no resistance) or they work!
Yours sound OK to me, and I think its a good move to time the heating interval next.
Its acceptable to unscrew a plug from the cylinder head and watch it glow, if you like.
John
thanks guys, wasnt going to take them out unless i have to, mechanic i spoke to said my car isnt usaly to bad with glowplug breakage where some models are more prone, but i can get 4 new for £55 so if i have to go to the trouble of removing them then ill not bother reusing them, and just bang in new for the sake of it.
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Sounds expensive, what car is it?
Easiest way to test old ones is to put them on the battery, if they dont glow they are knackered.
Easiest way to test old ones is to put them on the battery, if they dont glow they are knackered.
2008 vauxhall astra, price from local motor factors. iv heard some pople taking them out to see if they glow, wich i could do, but is it worth taking old out and puting back if there ok, or for the sake of it, (4-5 year old with 125,000 miles on them) is it worth banging new in?.
About £30 to £35 quid a set on ebay i reckon, its worth banging a new set in as you say. Try to buy branded such as bosch or something oe spec.
Its very difficult to get an accurate reading at that low level of resistance as a less than perfect contact can easily double the reading, with a good clean connection I normally reckon them to read about 1 ohm, you rarely get a lower reading but I would suspect that as they are all reading low that they are OK as normally they go high or open circuit. at .25 ohms the plug would be drawing 48 amps! if it was I think the wiring would let you know, I don't think it would manage 200 amps without some sign of serious overheating.
Peter
Peter
Have seen them cheaper online just with things for car prefer to go to local place. The ones priced for were NKG i think, again cheap or unbranded thigs can be troublesome cant it. Will double check the readings possibly today if i get chance, and give the metal work a good clean see if it alters reading.
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Or if you take a FUSED live lead from the + battery and tip the terminal of each plug you will see a spark as the current flows. Just don't touch the engine block/bodywork or you will blow the 30Amp fuse that you have in the lead. Don't hold them on to long, just 2-3 seconds
If hard to get at the terminal hold a long screwdriver on the terminal and tip the wire off the screwdriver
Don't go changing good plugs if they are all working, get the management light problem sorted first.
If hard to get at the terminal hold a long screwdriver on the terminal and tip the wire off the screwdriver
Don't go changing good plugs if they are all working, get the management light problem sorted first.
not had chance to check plugs, may do a spark test as in last post. Wont go changing good ones yet, only if i need to remove them i would. The managment light has a mind of its own, comes on.. then clears itself and so on evey now and again but garage has come up with code for glowplugs, but does clear itself, not to worried as its not a major engine issue but will sort it.
Hi guys, did a spark test and each give nice sparks so decided glowplugs are ok. However today i was driving fine then when i got back to return home went to start engine, all ok, then went to move off and had no steering, took 6 times to get round a corner, so pulled over switched off and switched back on and then all was well and drove home as usual.
This intermittant engine managment light coming on and off with no affect on driving the car, and todays power steering issue, Does anyone know what this could be? and could it be time for new battey? as far as i know its the origional from think april 2008 when car was built with 123,000 miles on it so over them miles and starting a diesel it may have had some stick? also battery has the green magic eye but iv been told to ignor that as they usaly wrong. Any help is welcome. thanks
This intermittant engine managment light coming on and off with no affect on driving the car, and todays power steering issue, Does anyone know what this could be? and could it be time for new battey? as far as i know its the origional from think april 2008 when car was built with 123,000 miles on it so over them miles and starting a diesel it may have had some stick? also battery has the green magic eye but iv been told to ignor that as they usaly wrong. Any help is welcome. thanks
Is it an electrical steering system on these?
2008 Astra
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