Glow plugs (Engine warning Indicator)

I have a 2006 TDI with 8000 km. and had the engine check indicator come on last week. I took it in and they replaced 2 glow plugs. After 3 days the check engine indicator came on again. The week prior to the first time I had the 8k oil change and it was a day or 2 after that the incator light came on the first time. I was wondering if anyone else has had problems with their glow plugs or something similar. I know that they put the new guy on the oil changes at the shop and wondered if he took something off and forgot to hook it back up again. I think that it was a new guy that decided that the glow plugs were gone. It is just freaking me out a little that the warning came on again and do not just want a quick replace the other two plugs and send me on my way. I am assuming that when they hook up the computer to get a read out on the problem it should be accurate enough to get to the real problem.

Any suggestions or info I should take with me to the shop would be appreciated.

Thanks

A couple of things: The glow plugs are numbered from rear to front rather than from front to rear. This may cause a problem if it says that #3 and 4 are bad so they replace the GPs on Cylinder #3 and 4.

The PD glow plugs are very fragile and extra care needs to be taken to keep them from becoming damaged.

Most often, the problem isn't with the Glow plugs themselves, but rather with connections. Have the shop check the Glow plugs with an ohm meter to verify they are bad before they replace them.

Glow Plugs

Thanks Whitedog I will mention that to them. I just read Wingnuts post on how to check the plugs so maybe I will check them then see what the shop says.

I was wondering if anyone else has had problems with their glow plugs or something similar.

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Kinda like asking 'is the pope catholic?'

I am assuming that when they hook up the computer to get a read out on the problem it should be accurate enough to get to the real problem.

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Thanks! I needed a good laugh today!

weedeater said:

Kinda like asking 'is the pope catholic?'

Thanks! I needed a good laugh today!

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The fault in the ECM only states the concern with a certain system, ie. glow plug fault. There are several parts of a glow plug system. Glow plugs, wiring, relays, and even modules. The fault does not will not narrow down the faulty part every time. It would be nice though. Ask your repair shop to have a lead tech involved with the repair since it is a "comeback" for all you know.

weedeater said:

Kinda like asking 'is the pope catholic?

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... well... is he?

whitedog said:

A couple of things: The glow plugs are numbered from rear to front rather than from front to rear. This may cause a problem if it says that #3 and 4 are bad so they replace the GPs on Cylinder #3 and 4.

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I think the PD engines are as they should be. Any one that I have scanned has had the plugs in the right order (code for #3 was bad @ #3). But anything is possible.

As already mentioned, it could be any number of components, but with such low mileage, I doubt it would be a harness issue. Considering the extremely fragile nature of these plugs, my hunch is the 2 that were installed bay have not been handled with care before instalation?

Make sure the dealer handles this one. You do not want to try to re & re the ceramic glow plugs yourself. I know from first hand experience not to touch PD glow pugs without a borescope now . I should edit my GP 101 thread to warn about these ceramic plugs.

wait a minute: this was a new '06 and they replaced plugs already?

1. hopefully they used the correct type since the newer motors use those stupid ceramic plugs.
2. hopefully the dealer was careful (ha!) when putting the new plugs in because they require special handling, else they can break.

Thanks Wingnut. I had a niggling feeling about that numbering system on the PD> Tonight, I'll pull a plug wire, start the car, get the light, then Vag it and see what poops up.

Yes it is an 06. I am taking it to the dealer on Wednesday so I will post the results. Thanks for the info wingnut! By the way why are the ceramic plugs more diffulcult to replace?? I do like the idea of being able to check the condition of the plugs myself. I am not an auto mechanic by any stretch of the imagination but I can almost fix anything so long as I have instructions or shown how it is done. I don't plan on doing a rebuild or anything but once it is off warrenty I do want to do most of the general maintenance myself. Might as well jump in with both feet!

The new ones are made of ceramic and are delicate. Search for the story here where they broke and fell into the cylinder. Not fun!

Sreeve,

They are not any more difficult to change than the ALH motors. If anything, they are easier as there are no fuel lines to get in the way. However, removing them is dicey as they are very fragile and if one is broken, it will fall in pieces into the cylinder.

Here is my experience with it:

http://forums.tdiclub.com/showthread.php?t=151070

Having said all that, if you want to test the plugs yourself, there is no danger in doing that. Just use a multimeter & test the resistance to see if the 2 new ones that were put in are the dead ones? But as I said before, let the dealer handle the re & re on this one.

I am not an auto mechanic by any stretch of the imagination but I can almost fix anything so long as I have instructions or shown how it is done.

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I have that problem with hoime projects too. I can almost finish anything.

OK. I pulled a plug wire, started the car and got no CEL...

OK. Dirve it for a bit.

Nope.

Hmmm check it with VAGCOM and there is the code for #1 GP, the one that I pulled.

So, no flashing light, but it did throw a code. I may do this in the AM and see if it flashes me with a cold engine.

It's a two trip code. It needs to see a failure twice before it turns on the MIL (CEL). If you plugged it back in you won't get an MIL and the code will clear after a real long time (40 trips on most cars).

Matthew_S said:

It's a two trip code. It needs to see a failure twice before it turns on the MIL (CEL). If you plugged it back in you won't get an MIL and the code will clear after a real long time (40 trips on most cars).

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So I need to pull the wire, start the car, turn off car, start the car?

BRB

Still nothing...

My #1 glow plug failed yesterday and it would only set the code when starting the car after it sat for a while. Also, a "trip" is more than just turning the engine off and restarting. A trip is starting the car below a certain temp allowing it to warm up to a certain point then shutting it off.

As I suspected. It needs a cold event to take place.

whitedog said:

As I suspected. It needs a cold event to take place.

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When I had a plug go on my PD, I got the emissions workshop message every time I started it. After the emissions workshop message went away the CEL stayed on.

During the day last summer, I cleared the code and drove it 5 miles or so. Turned the car off for 20 minutes and it came back with the next start until fixed.

Also to second Wingnut's warning as to the delicate nature of the PD glowplugs, the VW tech who put mine in at the dealer had the plug break in half as he tightened it. When my car is out of warranty, I'll suck it up and pay the dealer installation cost if/when my plugs fail.

So far the score of glowplug failures on my cars is:

2002 - 3 failed plugs
2005 - 1 failed plug

update on service

Just got back from the dealer and I asked the service manager about the ceramic GP and how they are known to crack. He said that he never heard about it before. Big surprise at the responce. Talked to the tech after he finished and he told me that he checked the GP's and they were fine so he replaced the harness. He said that he has seen this problem in some of the older models and that seemed to fix the problem. He was pretty confident about the fix but told me if it happens again he would change out the relays. I asked him about the problem with the ceramic GP and he said that yes they can be a real pain and has known some to crack. I guess we will see what happens over the next week or so. It took 2 or 3 days for the CEL to come on last time so time will tell.

Thanks for all the info guys it definately helps to go in informed.