coil pack

[drskunk]

my 2004 GXP is showing a cyclinder falt. I took it to the shop and they said it was cylinder 1 missfired due to moistur in the coil. They told me that the coils come in a pack of 4 and cannot be purchased seperatly. Is this true? should all 4 be done at the same time?

thanks,
drskunk

[J Wikoff]

Looking at Rockauto, it looks like the coil packs come in sets of 4 attached to a bracket. It may be the only way GM/ACDelco sells them. But it looks like they unbolt from the plate and individual aftermarket coils are available.

[drskunk]

thank you for the response. They are telling me that #2 is showing signs of moisture so i decided to have them all replaced. I love this car and want to be proactive to prevent any other issues with it.

[CMNTMXR57]

You should be able to purchase them separately. GM calls the aluminum bracket that all four mount to, the "Cartridge". You do not need to replace all 4 for 1 faulty one. Also, between the "cartridge" and the cam cover, there is a rubber grommet around the each hole (it effectively slides over the coil pack as it extends into the plug hole). Sometimes those can be worn/brittle, particularly if that particular coil was shorting out in anyway.

[PontiacFan]

You can replace each one individually if you want to.
But in the end, it would be money well spent to buy both sides, all eight, ..., & just move on with no more worries.
I tried replacing one or two at a time by using some from a salvage yard.
But the back side is so hard to get to, ..., if you're in the back, do it all at once & be done.
Yes, I learned the hard way & did one coil, then had to go back in a few weeks later & did the whole cartridge.

[CMNTMXR57]

For the back, just remove the EGR pump and it's just as easy as the front.

[fisdadsbonneville]

autozone shows pictures of them individually for $79 each or $159 for a full bank of 4. Ebay has AC Delco parts for these for $169 as well.

[DRWBRTq19]

There was a redesign in the coils.
Those individual ones are the new design, and unless you've already changed out the bracket, will not fit your current setup.

Drew

[CMNTMXR57]

What did they change? Looking it up in SI, which I updated through 2009 as well as GMPD, shows no difference in the part. They look identical and the coils can be individually removed from the aluminum bracket "cartridge".

Or are you saying a new bracket "cartridge" is needed to accomodate the redesigned coil?

[DRWBRTq19]

I believe the difference is in how the coils fit into the bracket.
I have to apologize for my uncertainty.
I don't actually own a GXP (yet, which is why I have so few posts), so I haven't handled the old style.
However I am a parts counterman, and just last month I was tasked with finding out why the new coil we had ordered for a customer (with an 04 I believe) didn't fit. The info I'm passing along is from the Wells tech department, who also informed me GM had made the change as well.

Hope this helps.

Drew

[CMNTMXR57]

No worries Drew. It's good info.

[DRWBRTq19]

Found it:
New OE design coil with horizontal connector replaces old design coil with vertical connector.
Must use C1509 coil assembly when replacing individual old design coil.

Drew

[CMNTMXR57]

Ahh, ok. So it's the electrical connector/pigtail to the cartridge harness. That would make sense as a lot of GM's newer CNP setups use a horizontal connector style coil.