When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I noticed that the grommet and plug show as items #9 and 10 in the diagram below are missing from the engine cooling shroud on my 95 993, at least on the right side of the engine. There is a corresponding hole/grommet/plug on the left side, but I can't see it. The right side can be seen by shining a flashlight in between #4 and #5 intake runners.
Have you observed this area on your 993? Parts present or missing? What is the significance of these parts? What is the purpose of the holes?
Both are rubber grommets with a hole to let pass the electric cables from engine Knock bridges, left and right
you can see them on my spare engine in pictures
Bobby, here's a few more pics which should explain further...
What is shown in the diagram is what I have circled in red. One on each side, they have a hole in the middle which allows a wire to pass through as geolab has mentioned. The one on the left is hidden a bit more between #1 & 2 intake tubes (see last photo)
I believe the hole you are referring to, which is empty (and the empty hole shown in the diagram) is actually an access hole to the bolt for the wire Geolab referenced. See circled areas in green on first two pics.
Hope that helps...
Last edited by boomboomthump; Mar 17, 2021 at 05:12 PM.
Thanks, geolab! There are no wires coming through the open hole on my cooling shroud, at least not on the right side. The car is a 1995 US model, always passes California's very strict smog inspections, no fault codes ever displayed, no faults show up on ScanTool runs. Does this engine not have knock sensing?
Hi Bobby T
It may be easier to put them in by removing the heater duct above the engine fan and reaching inside the tin and placing the grommet from the inside.
Andy
Actually, as far as I can tell, these smaller holes (20mm or so) are meant to be left open. They are to provide access to the knock sensor mounting bolt without having to remove the entire cooling shroud, in the event the knock sensor needs replacing. The holes shown in the diagram along with a grommet and plug are for the knock sensor wire to exit the cooling shroud. There is a similar arrangement on the left side of the engine, but all the way in the back, between cylinder #2 and #3.
So bottom line, all is well with my engine, nothing missing. Thanks for your suggestion.
Missing plug in cooling shroud?
