Fluid in spark plug bay?

[GMan]

Encountered an odd situation that I am clueless about while working on my '05 Envoy 4.2 I6.

Followed outlined steps to clean throttle body (big thanks to all the posts on that topic and it was VERY dirty). I figured since I had it all apart that I would also change the plugs. The plugs in cylinders 1(closet to radiator) through 4 were well worn and dry. When I extracted the plugs for cylinders 5 and 6(closet to firewall) the plug threads and tips were heavily coated in fluid. The fluid appeared much like clean motor oil (thick, slippery, slightly yellowish). I have to believe the fluid coated the plug as it was removed from its socket as the threads and tip were fully and apparently freshly coated, and thus assume the fluid was stagnant in the plug bay. The socket wrench nor the nut portion of the old plugs seemed to be coated. It was quite difficult to visually inspect due to the location, but I did not notice anything different between the various plug bays.

My truck runs substantially better after re-assembly, but concerned I have another problem that should be investigated further. Any thoughts or assistance would be much appreciated.

 

[dla442]

Typically there is dielectric grease in there and the intake shroud dips down towards those areas. Moisture and condensation and some times just rain from the hood cowl area gets on that shroud and drips water down there causing coil failures on the one particular coil.

 

[The_Roadie]

Valve cover gaskets can leak oil in there over time. I wouldn't worry about an ounce or less as long as it didn't totally fill up the well. Next time just check after you get the coil off and before removing the plug. Paper towels might work. Compressed air always does if you can deal with the blowback fluid. Too much liquid falling in the cylinder could bend things on next start-up unless blown out through the spark plug hole with a compressed air nozzle.

Water often gets in plug well #4 and 5 from cowl leakage. There's a TSB and GM redesign to seal it up and deflect water better.

 

[IllogicTC]

Valve cover gaskets can leak oil in there over time. I wouldn't worry about an ounce or less as long as it didn't totally fill up the well. Next time just check after you get the coil off and before removing the plug. Paper towels might work. Compressed air always does if you can deal with the blowback fluid. Too much liquid falling in the cylinder could bend things on next start-up unless blown out through the spark plug hole with a compressed air nozzle.

Water often gets in plug well #4 and 5 from cowl leakage. There's a TSB and GM redesign to seal it up and deflect water better.

If you notice it before having the plug off, you're much better off. Another case for checking the wells before beginning removal. I would suggest getting paper towels or shop rags or something, fit it over the top of the well with a little spot to fit the compressor wand in, and spray away. The towel should collect a lot of the fluid, and whatever hits the sides can then be wiped out.

 

[Gevans17]

Encountered an odd situation that I am clueless about while working on my '05 Envoy 4.2 I6.

Followed outlined steps to clean throttle body (big thanks to all the posts on that topic and it was VERY dirty). I figured since I had it all apart that I would also change the plugs. The plugs in cylinders 1(closet to radiator) through 4 were well worn and dry. When I extracted the plugs for cylinders 5 and 6(closet to firewall) the plug threads and tips were heavily coated in fluid. The fluid appeared much like clean motor oil (thick, slippery, slightly yellowish). I have to believe the fluid coated the plug as it was removed from its socket as the threads and tip were fully and apparently freshly coated, and thus assume the fluid was stagnant in the plug bay. The socket wrench nor the nut portion of the old plugs seemed to be coated. It was quite difficult to visually inspect due to the location, but I did not notice anything different between the various plug bays.

My truck runs substantially better after re-assembly, but concerned I have another problem that should be investigated further. Any thoughts or assistance would be much appreciated.

http://gmtnation.com/f23/need-know-what-new-hood-seal-looks-like-1068/