Replacing rear spark plugs.
- Bill's GXP
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Replacing rear spark plugs.
The fronts were as Rodney said " a piece of cake", but the rears look like a bi*ch. How and what do you need to remove that "sensor" mounted over the VC? Does that hose carry water? The other pipe, I have no idea where it goes. I see the bracket bolts are 10mm. Any help is appreciated.
2004 Bonneville GXP
One of 2,143 built and one of 300 in Liquid Silver.
One of 2,143 built and one of 300 in Liquid Silver.
- repinS
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Re: Replacing rear spark plugs.
No water involved, that's an air pump shutoff valve for emissions. From here: http://www.pontiacbonnevilleclub.com/fo ... 19774.html
Having been through the process myself, some of the fasteners will have to be done blind - and don't drop them down the back of the motor! Overall it wasn't too bad.CMNTMXR57 wrote:1) Remove strut tower brace
2) Remove Secondary A.I.R. shut off valve. This is the big piece in the center of the rear cam cover. You'll need a long extension with either a swivel or U-joint and a 10mm socket to get the nuts off the exhaust flange. From there, the same 10mm works on the bolts that hold it to the cam cover. You will need a 10mm wrench on the one bolt a socket can't get to. Disconnect A.I.R. feed from the pump (the big rubber hose).
Have at it... They replace the same as the front.
This is what I sent to you via PM. I thought you got it;
NP. It's the same as the front, except you need to remove the Secondary A.I.R. shut-off valve that sits right in the center, on top of the cam cover. And before that, I would remove the Strut tower brace. I believe that's a 13mm bolt. They're a threaded nut, so don't worry about having issue putting it back in.
You're gonna need some extensions, and a swivel or u-joint, with a 10mm deep well socket. This will be used to undue the nuts on the exhaust flange for that the Secondary A.I.R. system feed into. From there, a combination of a 10mm wrench and 10mm socket will undue the bolts holding it to the cam cover. Disconnect the electrical harness, as well as the feed tube from the Secondary A.I.R. pump.
With this, you can take it all off, put it aside, and you're free as you are in the front (sans a little tighter workspace.

Jerry /// Past: 95 SSEi (June 2010 COTM) -- 04 GXP (July 2011 COTM)
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- CMNTMXR57
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Re: Replacing rear spark plugs.
Saved me some typing. 

Retired Bonneville Owner and former GM Tech:
2004 Pontiac Bonneville GXP: Black/Ebony *SOLD*
Summer Toys: Combined 827 RWHP / 877lb/ft RWTQ
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Re: Replacing rear spark plugs.
get a small magnet and stick in your socket to get the nuts back on the AIR flange. You don't want to lose those. It looks like beyatch but it really wasn't that bad once I got into it.
- Bvill_GXP
- GXP Member

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Re: Replacing rear spark plugs.
Yea me and my buddy did mine and the rear really wasn't that bad.... We did find that the gasket on that AIR Flange thingy was not put on correctly and was causing air to escape b/c the area around it was black.... We cleaned it off and after the plugs was installed we put the gasket back in place ( matched up the screw holes )...
2005 Bonneville GXP Fully Loaded


- Nezzies 2005 GXP
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Re: Replacing rear spark plugs.
I used a small mirror to see the blind spots.


