How to change Glow Plugs on 05 LLY

[gmcfarm]

Hi Guys, I have search the site and can't find any how to pictures and/or instructions on how to change out the glow plugs on my 05 GMC LLY 127K. Onstar called me (while I was driving down the road) and told me I have a glow plug issue. I was not having any problems starting at the time (2 months ago) and was not showing any check engine soon light.
This morning she ran rough after starting for about 1 min and smoked pretty good. My code checker shows no code and I have no check engine lights also.
A) I need info on how to change the glow plugs out
B) Is it normal to show NO code or check engine light? (onstar knew something was up?
C) doe dealer have better code checker to tell me what is really goin on?
Thanks for the help in advance.

[tuney443]

Originally Posted by gmcfarm

Hi Guys, I have search the site and can't find any how to pictures and/or instructions on how to change out the glow plugs on my 05 GMC LLY 127K. Onstar called me (while I was driving down the road) and told me I have a glow plug issue. I was not having any problems starting at the time (2 months ago) and was not showing any check engine soon light.
This morning she ran rough after starting for about 1 min and smoked pretty good. My code checker shows no code and I have no check engine lights also.
A) I need info on how to change the glow plugs out
B) Is it normal to show NO code or check engine light? (onstar knew something was up?
C) doe dealer have better code checker to tell me what is really goin on?
Thanks for the help in advance.

Never had an on-star Dmax so I can't help you there,but changing glow plugs is about as difficult as changing a spark plug.Pull off both of your inner fender liners,SOAK both the small wire nut and the plug itself with PB Blaster,when you're ready to attack each plug,then spray CRC brand[same co. that makes Brakeleen] Freeze-off[comes in a tall light blue can--the cat's azz,trust me] on those 2 threaded areas and remove your plug.Put some anti-seize on the plug threads,some di-electric grease on the wire nut.X8 and you're done.Best price I found was at GM PARTS Direct--about $18 ea.--dealers are double that.Good luck.

[Shadow1]

How do you know the problem is the glow plugs and not the glow plug controller?

I'd keep checking for codes, on star must have seen a code to call you?

P0670 for glow plug controller

P0671 P0672 P0673 P0674 P0675 P0676 P0677 P0678 for glow plugs

Updated lly glow plug control module 97379635

[JC1843]

You can test the glow plugs with a multi meter-- the ohm should be around 10 ohm-?? You have to have the wire off to test-!

[tuney443]

Originally Posted by JC1843

You can test the glow plugs with a multi meter-- the ohm should be around 10 ohm-?? You have to have the wire off to test-!

It's app. 1 ohm,not 10.

[timoloco]

http://www.southwestcoalrollers.com/...ug-Replacement

Here is how to change the plugs on an LB7... so it should be pretty similar

[tuney443]

Originally Posted by timoloco

http://www.southwestcoalrollers.com/...ug-Replacement

Here is how to change the plugs on an LB7... so it should be pretty similar

That how to is somewhat flawed in that there is no reason at all to either remove the steering shaft or the down pipe for access to some of the GP's.It doesn't take a genius to use the correct extension,angle of attack,and just plain old common sense to do this.