I have 3 oil caps now. The new one I purchased on amazon looks slightly different. It has a bevel to underside edge (when you look at it upside down)



Here's the packaging it came in

Here is a photo of the one that came on my engine and one I found behind my engine when I did my s2000's first oil change (I'm the 5th or 6th owner). The newest one also has a 2 printed inside it.

The first two have damaged threads

I was thinking at first the rubber seal was different too... but after thinking about it a tiny bit more I realized the new one just has a fresh seal and the first two's seal has just been pressed flat.
Any experts or oil cap OCD experts out there know if this new one I have is genuine?

 

I just noticed the one I found behind my engine that says A13 inside instead of 2 also has AP1 SJ (or API) on the cap that the others don't have.

 

I have no expertise in recognizing a fake oil cap, but I would say if it works it works. Put it on, drive around, make sure it does not loosen. If not, it likely is ok Generally the oil cap on this car will tighten quite a bit after you put it on, not loosen. I tighten mine with two fingers, have to use my hand to take it back off.

I would upgrade to a 710 cap though. I hear those are the bomb ....

 

@engifineer I'll try the 710 cap when I refill my blinker fluid & change the summer air in my tires for winter air.

 

Just ordered a new one, its been on the list

 

Looks genuine to me.

Yep the flat seals are because they're old and probably fossilized. Replacing the seal (15610-pcx-a01) is simple and inexpensive ($6) but the complete cap isn't much more ($12). I replaced my oil cap a couple years ago as it took giant pliers to get the original off. Was the rubber seal I suspect.

The part number is indeed 15610-pcx-a01 for all model years and the marking inside is probably a die number from the machine is was produced on.

-- Chuck

 

I heard someone mention this before when talking about counterfeit items: "where's the value in counterfeiting something like this". It's not like it's a high value item that can net some amazing returns.

 

My new one has the bevel as above,looks like its de-shamferd from manufacture process to remove sharp edge.