04 GMC Envoy Vortec 4.2L spark plug change....

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#1
I've looked for a technical bulletin or a service manual for this car and it doesn't seem to exist.. I need the procedure for "Undressing" the engine so I can get to the plugs and wires...I'm getting a error code "P0306" which is a misfire in # 6 cylinder..Any idea where I can get technical info--a service manual--step by step instructions--or etc.....TIA
 
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#2
try alldata.com.
there is a link in the red banner on page
next source would be from GM....there is a page in owners manual for ordering manuals (cd)
 
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#3
it seems very easy my friend. Just remove the the two 10mm bolt that holds the air dam and unscrew it on the throttle body. just be carefull not to break the vacuum hose from fuel regulator. thats it you will see a line of six ignition coils.

note:
try to check the plugs for carbon cracking, and do elimination method to verify the problem. try to swap one coil to onother to to verify. Also the boot is replacable sometimes it breaks open. but make sure the compression pressure is good min of 150 psi or else it useless. u wont solve the missfire.

thanks
mj