Glow plug warning

[drover]

I will ask my Wait Awhile mate over there who he gets to do his, he has fallen apart due to age so doesn't play with spanners anymore ............. I look for a Tranny Shop that does ZF tranny's, look for BMW's, Landy's etc in the forecourt, brakes by a brake shop etc, rarely use a general mechanic at all, though I do most of my own but am slowly hanging up the tools...... My Grands have been basically oil and filter changes with no real problems over the 3 of them which has been about 500,000kms I suppose, the odd CV boot and I think a rear bearing on one but nothing nasty. .................. Many years on AJOR certainly gives you a heads up on most possible problems and solutions..... If mine does have a problem then a Jeep dealer wouldn't be on the radar as they are too far away....

[chooke]

So the Jeep was due for a service so this time took it to another independent and asked them to look into the glow plug flashing light issue. It looked promising as the guy who runs the shop also owns a WK2 (V8 though).

Just a reminder, the issue is that sometimes the glow plug light in the dash flashes after start up and continues until the engine is next restarted. While it does this intermittently, it is not random because when it does it is typically after the car has been sitting overnight (or after several hours of sitting in very cold weather).

Their scan came up with the same code as previously of a glow plug in cylinder 3. Like with the dealer they were unable to specifically locate the issue. The circuits measured fine and so did the actual glow plug. He suggested it could be the glow plug control module if I wanted to take a punt. So I replaced the module and it didn't fix it.

I went back to the Jeep dealer earlier today to find out a bit more on what they did after their diagnostics 6 months ago (when they said they needed the car back to do a deeper dive). I asked their technical service person that since I replaced the controller module, does that mean it must be that the glow plug is the issue?

They suggested it could be because I have a leaky manifold (which I think is the flap valves issue they identified five years ago...) or any number of things which will require further investigation. So I asked what if it is the glow plug, is that something that can be changed over fairly quick? They told me, no because it is cylinder 3, half of the engine would need to be stripped, including removing the manifold. They quoted me 7 to 8 hours of work and around $400 in parts.

This doesn't sound right to me, so what do you think?

Do you also think it is the glow plug or some other issue?

Lastly, as a last resort I am thinking of just having the dash light disconnected as the car runs fine. Is this likely to cause other issues, such as a CEL?

Thanks, this is so frustrating.

[layback40]

Originally Posted by chooke

Their scan came up with the same code as previously of a glow plug in cylinder 3. Like with the dealer they were unable to specifically locate the issue. The circuits measured fine and so did the actual glow plug. He suggested it could be the glow plug control module if I wanted to take a punt. So I replaced the module and it didn't fix it.

I went back to the Jeep dealer earlier today to find out a bit more on what they did after their diagnostics 6 months ago (when they said they needed the car back to do a deeper dive). I asked their technical service person that since I replaced the controller module, does that mean it must be that the glow plug is the issue?

They suggested it could be because I have a leaky manifold (which I think is the flap valves issue they identified five years ago...) or any number of things which will require further investigation. So I asked what if it is the glow plug, is that something that can be changed over fairly quick? They told me, no because it is cylinder 3, half of the engine would need to be stripped, including removing the manifold. They quoted me 7 to 8 hours of work and around $400 in parts.

This doesn't sound right to me, so what do you think?

Do you also think it is the glow plug or some other issue?

Lastly, as a last resort I am thinking of just having the dash light disconnected as the car runs fine. Is this likely to cause other issues, such as a CEL?

Thanks, this is so frustrating.

The wire between the module & the GP is all that is left.
Depending on how it flashes, it could be a short to earth. Bare wire rubbing?
If they are testing, probably they are not seeing the problem when testing. If the GP has the appropriate resistance, it should not be the cause.
Good Luck!

[chooke]

Originally Posted by layback40

The wire between the module & the GP is all that is left.
Depending on how it flashes, it could be a short to earth. Bare wire rubbing?
If they are testing, probably they are not seeing the problem when testing. If the GP has the appropriate resistance, it should not be the cause.
Good Luck!

Thanks. I'm certainly in a bind as both the Jeep dealer and the independent shop tested the wiring and GP to be ok. That's why the independent then suggested if I wanted to take a punt, replace the control module. That didn't resolve it so there is nothing else and if it really is a 7hr job to replace the cylinder 3 GP then disconnecting the GP light in the instrument panel is probably the best option (if it can be done) as whatever the 'fault' is it is not affecting the operation of the engine.

[TR Laredo]

Might be worth buying a new glow plug & temporarily connecting it up to number 3's wiring & earth to see if the problem goes away during the start cycle. Just make sure you don't have the glow end sitting on anything flammable when you power it up.
From Rockauto glow plug details for a 2015 model are BOSCH 0250603008:

https://www.sparesbox.com.au/product...aIQobChMI0Iuv-
MyPgwMVR6JmAh2OVAy8EAQYAiABEgJBP_D_BwE

https://www.rockauto.com/en/catalog/...glow+plug,7152

[chooke]

Originally Posted by TR Laredo

Might be worth buying a new glow plug & temporarily connecting it up to number 3's wiring & earth to see if the problem goes away during the start cycle. Just make sure you don't have the glow end sitting on anything flammable when you power it up.
From Rockauto glow plug details for a 2015 model are BOSCH 0250603008:

https://www.sparesbox.com.au/product...aIQobChMI0Iuv-
MyPgwMVR6JmAh2OVAy8EAQYAiABEgJBP_D_BwE

https://www.rockauto.com/en/catalog/...glow+plug,7152

That's an idea that could be worth trying. The only problem with that is the light flashing does not happen with each overnight start. It happens around 30% of the time so even if I don't get the flashing say after a week of doing this everyday it may still be inconclusive. For example, when I replaced the controller module I thought that probably did the trick as I didn't get the light flashing for several days.

[drover]

If the glow was tested correctly then I doubt it is the culprit, glow plugs work or don't, sounds more like a possible bad canbus connection which is causing the light to throw not actually the operation circuit...

But at $40 from Supercheap why not give it a go....https://www.supercheapauto.com.au/p/...PO3726510.html

It would drive nuts for sure.......

Having to remove the manifold to get to them ,stupid design.