Author Topic: MY WAY OF TESTING A GLOW PLUG???  (Read 4241 times)

Offline matping

  • Here all the time
  • ****
  • Posts: 415
  • MK1 20vT MK5 GTI T
MY WAY OF TESTING A GLOW PLUG???
« on: 13 September 2011, 21:08 »
can anyone confirm what i do is correct  what i do first is
1 . put my multimeter on the battery both terminals to get a voltage i only do this really to see if the muti meter is working then i
2 .leave the red probe on the pos terminal of the battery and touch the top of the glow plug with the negative probe  then im
3 . looking for a reading of roughlly what the car battery is  12.5v

thankyou    matt

Offline danny_p

  • Forum addict
  • *
  • Posts: 4,646
Re: MY WAY OF TESTING A GLOW PLUG???
« Reply #1 on: 14 September 2011, 23:52 »
nope.

that'll just tell you that one or more plugs are grounding.

you need to discoonet the bizz bar from them then measure the resitance of each one, that will give you a far better idea,   reaally the best way to test is to see how much current they pull but your average multimeter would get very upset if you tryed to measure the currents involved with it
all the VW's have gone bar 1.

Offline matping

  • Here all the time
  • ****
  • Posts: 415
  • MK1 20vT MK5 GTI T
Re: MY WAY OF TESTING A GLOW PLUG???
« Reply #2 on: 15 September 2011, 19:45 »
whats the best way of testing resistance then bud

Offline danny_p

  • Forum addict
  • *
  • Posts: 4,646
Re: MY WAY OF TESTING A GLOW PLUG???
« Reply #3 on: 18 September 2011, 10:12 »
remove the buzz bar connecting all 4 plugs together,

then neasure the resitance from the tit on the end of each plug to the the engine block
all the VW's have gone bar 1.

Offline javalin

  • I live here
  • *****
  • Posts: 1,457
Re: MY WAY OF TESTING A GLOW PLUG???
« Reply #4 on: 20 September 2011, 10:44 »
google is your friend.

http://www.ngk-dpower.com/index.php?id=31&L=2

http://www.therevcounter.com/mechanics/46288-testing-glowplugs.html

Testing glow plugs is easy and can be done with them still installed in the engine. Just disconnect the wire going to each glow plug. Connect a test light to the POSITIVE (+) battery terminal and touch the point of the test light to each glow plug terminal. If the light lights, it's good. If it doesn't, it's bad and needs to be replaced. Do you replace just the bad one or all of them? My opinion is that if one went bad, then the rest are not too far behind. So I recommend replacing all of them at the same time.


And yes - get a set of four if one/some have failed.

Note - NOT an LED test light - one like:

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=380171397677

James
You only ever need two tools in life. If it moves and it shouldn't use Duct Tape. If it does not move and it should, use WD40.

Offline dilbert

  • GTI forum regular
  • ***
  • Posts: 201
Re: MY WAY OF TESTING A GLOW PLUG???
« Reply #5 on: 25 September 2011, 22:17 »
a good way of testing the glow plugs is a ohms resistance test which should read up around 0.6 - 0.9 ohms anything over or under will mean a faulty glow plug.

take out the glow plugs,
get your multimeter set to ohms
place the earth lead (black) on to the side of the glowplug where the thread is, and the live lead (red) onto the top of the glow plug where the live feed connector clips/bolts on and check your readings on the multimeter
mk4 golf 1.8 gti 20v