Technical Glow plug help

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Technical Glow plug help

1990dtl

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my punto will not start just happened without warning. one day wouldnt start and hasn't done for the last 3 weeks. my mate says its glow plugs but he wont do them cos they look a massive job. iv had a look myself and i agree how the hell do you get at them? pictures would help if anyone has any . Thanks

its a punto 1.9 elx jtd 2002
 
Better to describe what happens when you try to start it, most diesels will start without the glow plugs if you crank it for long enough

Better to be 100% on the cause before doing work which might not help
 
Some glowplug when they are dying need a little help

When you put the ignition on - the preheat begins of the air in the combustion chamber
Give the car a helping hand
Let the glowplug warm up - till light on dash goes out
Switch ignition off
Ignition on - wait till GP light goes off
Ignition off
Guess what - ignition on again :)
Wait till it goes out and THEN CRANK

By doing it 3 times, a weak plug might have just helped with warning up :)

glowplugs often seize into the block - they need a quality penatrating oil to help with them

Some people reported good success with a week in advance treatment - with repeated treatments daily

The Hot cold hot cold allows the oil to start to seap in and loosen/aid removal

For love and god sakes money - DONT SNAP THEM

snapping them is either
A - leaving them snapped and insulating its terminal
B - Head off to have it drilled and retapped

Ziggy
 
Im 100% sure its the glow plugs it turns over just will not fire up I want to get them out to test but how do you get at them ?
 
Im 100% sure its the glow plugs it turns over just will not fire up I want to get them out to test but how do you get at them ?

As I said the glow plugs just aid starting especially in cold weather, you can still start a diesel without working glow plugs which is why I questioned if this was the issue

Also you will get the glow plug light flashing at you for absolutely ages if they are not working, again not that this matters because the car should still start if you crank it over for 30seconds to a minute
 
As I said the glow plugs just aid starting especially in cold weather, you can still start a diesel without working glow plugs which is why I questioned if this was the issue

Also you will get the glow plug light flashing at you for absolutely ages if they are not working, again not that this matters because the car should still start if you crank it over for 30seconds to a minute

Ah well I cant start it the battery drains before it starts breakdown said it will be glow plugs and so did my mate who is a mechanic but if you think otherwise what could it be?
 
If you're not getting a flashing glow plug light, and the light comes on and goes off as you would expect then it's not the plugs.

It's a long time since I had my 1.9 but I don't remember them being very difficult to get to.

You can check em one by one with a multimeter should be about 7Ohms each? (Something like that)

But it could be an electronics issue, could be a knackered fuel pump or could even be the immobaliser,

This is why I said to post what's actually going on when you try and start it, or else you could spend £50 and a lot of perfectly good knuckle skin changing glow plugs that are actually fine and still have a non running car
 
If you're not getting a flashing glow plug light, and the light comes on and goes off as you would expect then it's not the plugs.

It's a long time since I had my 1.9 but I don't remember them being very difficult to get to.

You can check em one by one with a multimeter should be about 7Ohms each? (Something like that)

But it could be an electronics issue, could be a knackered fuel pump or could even be the immobaliser,

This is why I said to post what's actually going on when you try and start it, or else you could spend £50 and a lot of perfectly good knuckle skin changing glow plugs that are actually fine and still have a non running car

Its apparently a 3 hour job to get at them the car does not have a glow plug light so I cannot go off that all I know is its been fine for 2 years iv owned it no problems I took it for mot it failed and day after it wouldnt start and hasnt done since. Well day after mot it started after 20 mins of turning over then a week later of not starting breakdown started it after 45 mins and that was last I seen it started
 
Hi,

I Agree with Andy. Its very rare for glow plug problems on a JTD to cause a no start. JTD's do not rely on the glow plugs like the Multijets do, and can start with no glow plugs. Im not saying it doesnt happen, but its best to diagnose correctly before running the risk of snapping a plug.

Secondly, you WILL have a glow plug light. Its a little yellow "coil" shaped light. It should come on when you turn the key to MAR, and then go out for a few seconds. If it detects a fault in the system then it will flash for 10 seconds.

As Andy says, before you attempt to remove the glow plugs, you should test their resistance in situ. You can tell if they are fault or not without removing them and the risks associated with it. You can test either each individual plug, or you can remove the multi plug from the bottom of the control box and test them that way without having to even get at the plugs themselves.

A common cause of pre heat system problems on the JTD is in fact the control box rather than the plugs themselves.
Its located on the rear fire wall just behind the EGR valve. Again, another reason why you should test the plugs first before attempting to remove.

The glow plugs are not too difficult to remove on a JTD, although number 4 can be a bit tricky. Long reach socket and extension bar, set of long nose pliers. There are even little cut outs in the inlet to help a bit.

Have you checked the Maxi fuse for the pre heat system?

Have you checked the main earths from battery to engine etc?

What is the background to this fault?

Ie had it been getting more difficult to start recently?

Running any differently?

Engine management light illuminated?

Is they key code light going out when the ignition is turned to MAR?

As Andy says there are a number of things that it could be,

Faulty Crank sensor
Faulty LP pump
Faulty HP pump
Fuel Rail pressure sensor
MAF.

All of them could be causing the problem your experiencing.

What diagnostics have been done to the car so far? Do you have access to any diagnostic equipment?

Alan
 
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Hi,

I Agree with Andy. Its very rare for glow plug problems on a JTD to cause a no start. JTD's do not rely on the glow plugs like the Multijets do, and can start with no glow plugs. Im not saying it doesnt happen, but its best to diagnose correctly before running the risk of snapping a plug.

Secondly, you WILL have a glow plug light. Its a little yellow "coil" shaped light. It should come on when you turn the key to MAR, and then go out for a few seconds. If it detects a fault in the system then it will flash for 10 seconds.

As Andy says, before you attempt to remove the glow plugs, you should test their resistance in situ. You can tell if they are fault or not without removing them and the risks associated with it. You can test either each individual plug, or you can remove the multi plug from the bottom of the control box and test them that way without having to even get at the plugs themselves.

A common cause of pre heat system problems on the JTD is in fact the control box rather than the plugs themselves.
Its located on the rear fire wall just behind the EGR valve. Again, another reason why you should test the plugs first before attempting to remove.

The glow plugs are not too difficult to remove on a JTD, although number 4 can be a bit tricky. Long reach socket and extension bar, set of long nose pliers. There are even little cut outs in the inlet to help a bit.

Have you checked the Maxi fuse for the pre heat system?

Have you checked the main earths from battery to engine etc?

What is the background to this fault?

Ie had it been getting more difficult to start recently?

Running any differently?

Engine management light illuminated?

Is they key code light going out when the ignition is turned to MAR?

As Andy says there are a number of things that it could be,

Faulty Crank sensor
Faulty LP pump
Faulty HP pump
Fuel Rail pressure sensor
MAF.

All of them could be causing the problem your experiencing.

What diagnostics have been done to the car so far? Do you have access to any diagnostic equipment?

Alan

how do i test them in this control box and what does it look like please? iv been told to get the glow plugs out all the injectors and crap on top have to be unplugged, unbolted and all the jubilee clips have to be cut off to remove all the black tubes out the way also, because you have to remove the wire running along the top of them to be able to get the socket on the glow plugs themselves, is this not right then?

the car wasnt running any differently before it stopped was all fine before it went in for M.O.T. there are no engine lights on and no codes. only diagnostics are breakdown and my mate who both are positive its the glowplugs im not a mechanic so i cant comment really i know very little about cars i just know how few things work and i can change service parts and sensors etc i can only go by what iv been told on this one.
 
how do i test them in this control box and what does it look like please? iv been told to get the glow plugs out all the injectors and crap on top have to be unplugged, unbolted and all the jubilee clips have to be cut off to remove all the black tubes out the way also, because you have to remove the wire running along the top of them to be able to get the socket on the glow plugs themselves, is this not right then?

the car wasnt running any differently before it stopped was all fine before it went in for M.O.T. there are no engine lights on and no codes. only diagnostics are breakdown and my mate who both are positive its the glowplugs im not a mechanic so i cant comment really i know very little about cars i just know how few things work and i can change service parts and sensors etc i can only go by what iv been told on this one.

so you've tried the "heating 3 times cycle" and it's made ZERO difference..??

you SHOULD have a yellow symbol on the dash ( like a pair of specs) coiled wire,
IF you don't then there is an issue..,

Charlie - Oxford
 
so you've tried the "heating 3 times cycle" and it's made ZERO difference..??

you SHOULD have a yellow symbol on the dash ( like a pair of specs) coiled wire,
IF you don't then there is an issue..,

Charlie - Oxford

yes the glow plug light works and engine management light but they both go off........
anyone have a picture of this control box and how to test plugs through it.
 
yes the glow plug light works and engine management light but they both go off........
anyone have a picture of this control box and how to test plugs through it.

Hi,
pretty sure you could just put a meter onto the plug caps, seeing if they get power (when the light is on)

- so cycling the heat in the plugs still doesn't help ??
 
Hi,

Look at this GUIDE i made on where things are on the JTD. Its on the bulkhead behind the egr as i said. Its labled "cold start control box"

Its secured to the bulkhead with a 10mm bolt. Remove the bolt to move the box away and get to the multi-plug underneath.

You want to test the resistance of each glow plug. This will tell you if they are good or not. The reason i suggest doing it at the control box is that its much easier than trying to get a meter probe down onto the glow plugs themselves.

Do you have a multimeter which can measure resistance?

Did you check the Fuse for the cold start system?

Did you check any of the other bits i mentioned yet?

Alan
 
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Ok i will try that later today, its looking like im going to have to scrap it such a shame cos its a really good engine if i could get it going but its not worth spending money on "trial and error" glow plugs alone are £77 for 4 and if it doesnt fix it iv then got to go through other parts.
no the heating cycle does nothing iv mentioned to my friend what people in this forum have said(the one that guarenteed me it was a glow plug issue) that it cant be the glow plugs and he says it can and is because something to do with diesel in this country is crap and it needs the glow plugs to heat it to start the engine so if there gone it wont start? anyone think that he is wrong?
 
Hi,

Look at this GUIDE i made on where things are on the JTD. Its on the bulkhead behind the egr as i said. Its labled "cold start control box"

Its secured to the bulkhead with a 10mm bolt. Remove the bolt to move the box away and get to the multi-plug underneath.

You want to test the resistance of each glow plug. This will tell you if they are good or not. The reason i suggest doing it at the control box is that its much easier than trying to get a meter probe down onto the glow plugs themselves.

Do you have a multimeter which can measure resistance?

Did you check the Fuse for the cold start system?

Did you check any of the other bits i mentioned yet?

Alab

first thanks for time in helping me with this with your replies.
Iv checked all in car fuses and under bonnet all look fine dont think there are any more fuses anyway unless cold start fuse is separate to all other fuses. Funny enough before when i could get the car started after it got to operating temperature i could pretty much start it all day first time after the initial start just now i cant get it to start at all.
I have not checked the other bits you mentioned now as there is no engine light on so no codes so they all must be ok?
Faulty Crank sensor
Faulty LP pump
Faulty HP pump
Fuel Rail pressure sensor
MAF.
 
Hi,

I really wouldnt go buying glow plugs until you have tested them, as you say they are not cheap and there is risk associated with replacing them and it doesnt look like they are your problem anyway.

The diesel in this country is perfectly fine (better than most). I assume your friend isnt familiar with the JTD unit and its traits. As Andy has said, even with no glow plugs, it should still start.

Where abouts are you located? As one of us may be able to pop along and have a look for you.

Unfortunately, no engine management light doesnt mean that the things i mentioned are ok. A faulty crank sensor for example wont give an EML from start conditions, same with a maf out of tolerance, or a faulty LP pump etc.


Alan
 
Last edited:
Hi,

I really wouldnt go buying glow plugs until you have tested them, as you say they are not cheap and there is risk associated with replacing them and it doesnt look like they are your problem anyway.

The diesel in this country is perfectly fine (better than most). I assume your friend isnt familiar with the JTD unit and its traits. As Andy has said, even with no glow plugs, it should still start.

Where abouts are you located? As one of us may be able to pop along and have a look for you.

Unfortunately, no engine management light doesnt mean that the things i mentioned are ok. A faulty crank sensor for example wont give an EML from start conditions, same with a maf out of tolerance, or a faulty LP pump etc.


Alan

ok, I live in wrexham north wales.
what would be your suggestion can i only check other parts by replacing them with no eml light? should i just cut loses now and scrap it
 
If you're not getting a flashing glow plug light, and the light comes on and goes off as you would expect then it's not the plugs.

It's a long time since I had my 1.9 but I don't remember them being very difficult to get to.

You can check em one by one with a multimeter should be about 7Ohms each? (Something like that)

But it could be an electronics issue, could be a knackered fuel pump or could even be the immobaliser,

This is why I said to post what's actually going on when you try and start it, or else you could spend £50 and a lot of perfectly good knuckle skin changing glow plugs that are actually fine and still have a non running car

finally checked my glow plugs they are reading 0.7-0.8 all of them the guide says they should read 1.2 so is this why the car wont start should i now go out and buy glowplugs?
 
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