On the v6 cars, what is that gasket (and PN!) at the opposite side of the cam gear? The one that sits directly behind the EGR valve. And is there two identical ones, one for the front head and one for the rear head? I'd only imagine so...
This is camshaft holder cap seal (O-ring)
I changed mine last summer because it was leaking
{Added}: and its only one from the side you've shown. But my recommendation is still buy two O-rings as a back up, because it is very finicky to get it in and close that cap. High posibility to damage the O-ring during the process of replacing it. This is what happened to me. Luckily, I was smart enough to buy two of those
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