Page 1 of 4

How To: Check & Change Glow Plugs

Posted: Sun Aug 24, 2008 7:56 pm
by dry_flood
If you ever get the "check Injection" message on screen then this is the first thing to do before taking the car to a garage.

Do this while the engine is fully warmed up, it will make it easier to remove the glow plugs if you need to change one. It is advisable to wear gloves as obviously the engine is hot

Tools Required:
10mm Deep Thin Socket
Socket Extension Bar
WD40
Multimeter

Time required:
10 minutes to check all 4 glow plugs
5 - 10 minutes to change 1 glow plug


Lift The bonnet
Image


Undo the two 10mm bolts at the top of battery cover. The bolts need to be fully removed but be careful as the clip on nuts underneath can fall off into the engine bay. The battery cover flicks over to the left.
Image


Turn your Multimeter to 20 Volts and place the probes on the corresponding battery terminals. I.e. red probe to red terminal, black probe to black terminal.

You are doing this to check the voltage of your battery.
Image

My battery is currently showing 12.67 Volts. Write down the voltage your battery is showing.
Image


The engine cover is held down by 3 push clips underneath. To remove it you just hold onto it and lift.

The yellow circles below show the position of the glow plugs.
Image


The glow plugs are covered with a black plastic connector with a wire going into them.
Image


Holding the black plastic connector (do not hold the wire) gently pull the connector off the glow plug
Image


Now get the red probe from your multimeter and place on the red battery terminal. Hold the black probe on the top of the glow plug.
Image


Check the voltage displayed on the multimeter. It should be exactly the same or very near to the voltage you wrote down earlier. If it is more than 2-3 volts lower then it could be on its way out and It would make sense to change it now while you already have everything dismantled.
Mine was showing 0.00 volts so was definatley dead.
Image


Get your 10mm deep thin socket and extension bar. Place it on the glow plug and turn anti clockwise.
warning: Do not try and force it to turn.
If it will not turn then give it a squirt of WD40 and leave it for 5 mins. Keep giving it little turns and a squirt until it is easier to turn. Eventually it will come out.
Image


Below is the glow plug I removed
Image


You can purchase glow plugs from any good motor factor. My replacement cost £11. You can buy them cheaper online but I couldnt be bothered to wait.

Insert the new glow plug into the hole. Carfully screw it in by hand. Do not cross thread it!!!! It is very costly to have rectified. Once it is finger tight, use the socket to nip it up. Do not over tighten it, again this can cause problems.
Image


Check the voltage of the new glow plug in exactly the same way as you tested the old one. My new glow plug is showing the same voltage as my battery. Yours should too.
Image


Reconnect the black plastic connector, you will feel it click
Image

Double check that you have reconnected all of the connectors and have removed all your tools from the engine bay.
Start your car. If the "Check Injection" message is still showing then disconnect the battery and leave for 15 mins. This will reset your ECU Make sure you have your radio code first
In most cases it will not be necesary to disconnect the battery but sometimes the ECU will store the error code and display it everytime you start the car.

Replace the engine & battery covers.

Now all you have to do is pat yourself on the back and think about the money you have just saved. :beer

Gaz

Re: How To: Check & Change Glow Plugs

Posted: Mon Aug 25, 2008 10:13 am
by DJC013
Great post ! And the pictures help a lot , regards Damian. :-)

Re: How To: Check & Change Glow Plugs

Posted: Mon Aug 25, 2008 11:55 am
by Toosh
Brilliant post flood :cool:

Will remember this thread when mine pack in, which they will :-(

Re: How To: Check & Change Glow Plugs

Posted: Mon Aug 25, 2008 3:43 pm
by andywills
it's posts like this that should be locked onto the top of the forum, good work :-)

Re: How To: Check & Change Glow Plugs

Posted: Mon Aug 25, 2008 4:56 pm
by WebCode
Yes a Good post, but let me add another way of testing the plugs ..

Remove the glow plug connectors. Set the meter to Ohms. Put one probe on any convenient point on the cylinder head and the other on the glow plug centre.. If the Impedance (resistance) is any more than 2.5ohms then the plug is on the way out.

Remove it and replace..

99% of defective plugs will be "open circuit" so will show NO resistance at all.. It is rare that these high current plugs "partially" fail..

Also check that the factor gives you the correct voltage plugs.. There are some 6 volt ones that look the same, but they will burnout as soon as you turn the ignition on.. The voltage is stamped on the body of the plug.. Either 6v or 11/12v

Re: How To: Check & Change Glow Plugs

Posted: Mon Aug 25, 2008 5:41 pm
by dry_flood
your all welcome. Now if only someone could shed some light on my latest issue http://www.meganeownersclub.co.uk/forum/viewtopic.php?f=2&t=6951&start=60

Gaz

Re: How To: Check & Change Glow Plugs

Posted: Mon Aug 25, 2008 6:48 pm
by terry_mccann
Great howto...cheers mate....

Re: How To: Check & Change Glow Plugs

Posted: Mon Aug 25, 2008 9:53 pm
by AlexB
For glow plug checking/removal/installation instructions see p.295 in MR364MEGANE1.PDF (French):
https://www.reno.ro/index.php?s=e7cc151c ... 1627461167

The most important bit there is the torque value, which should be 15 N*m. When removing a glow plug, do not apply more than 2x of this figure -- cancel the job if they are seized! Apply some anti-seize paste to the thread of the new plugs.

I also remember, that I chose a 1/4 inch extension bar for easier access (1.9dci F9Q-800 engine).

For my engine the following plug is OEM:
Beru
0 100 226 373
GN 018
11V
(GSF reference was R18822)

Re: How To: Check & Change Glow Plugs

Posted: Fri Nov 14, 2008 6:17 pm
by Ray
stickied by request

Re: How To: Check & Change Glow Plugs

Posted: Sun Nov 23, 2008 12:57 pm
by jamie.osborne
Does anybody know if a "how to" has been done for the 1.9DCi (circa 2005) ? I need to replace the glow plugs and there is a plastic cover over the injection pipes and the heater plug location which "appears" to be held in place, after removing all fixings, by an inlet pipe. Unless there is some trick, it seems that this inlet mechanism might need to be dismantled, but I hope I am wrong.

Here's hoping

Jamie

Re: How To: Check & Change Glow Plugs

Posted: Sun Nov 23, 2008 2:52 pm
by busternlouie
Use the table below to identify your engine:
Image
Where "X" is "B" = 5dr "C" = 3dr
Now check the code in the top corner to see which air duct guide to use.

This one...
Image

or this one...
Image

Now use this guide to change the glow plugs:
Image

Re: How To: Check & Change Glow Plugs

Posted: Sun Nov 23, 2008 8:02 pm
by jamie.osborne
Thanks busternlouie, it is as I thought. Your post and the rest of this thread have been extremely helpful.

Many Thanks

Jamie

Re: How To: Check & Change Glow Plugs

Posted: Sat Nov 29, 2008 9:51 pm
by wabybaby
Hi

Great post I followed it and it was nice and simple to do thanks to your pics. Does anyone know what causes the glow plugs to go in the first place? Had my car about 2 months and replaced a full set on purchase and then a single one this weekend... Just wondered if I may have a fault somewhere else down the line causing these to go so often..

Re: How To: Check & Change Glow Plugs

Posted: Mon Dec 01, 2008 5:33 pm
by busternlouie
wabybaby wrote:Hi

Great post I followed it and it was nice and simple to do thanks to your pics. Does anyone know what causes the glow plugs to go in the first place? Had my car about 2 months and replaced a full set on purchase and then a single one this weekend... Just wondered if I may have a fault somewhere else down the line causing these to go so often..


All glow plugs have a limited life span and will eventually burn out, much like the element in fan ovens. However they should last longer than two months. Its possible that the plug changed over the weekend was faulty, or maybe the heater plug relay is stuck causing the plugs to be on all the time. You need to check if you are still getting a 12volt supply at the plugs a fair while after the light has gone off the dash.

Re: How To: Check & Change Glow Plugs

Posted: Tue Jan 27, 2009 1:37 pm
by ootmatree
Brilliant post mate. I have recently cleaned my egr on my megane1.5dci '04 plate, but I still have the lack of power problem when the car reaches 50mph any ideas? I've heard it may well be the high pressure diesel pump disintegrating.....not worth thinking about. cheers
clarky