Cylinder head valley plug question


New Member
Aug 25, 2020

I'm in the process of swapping the ignition system over to 2NZ coil-on-plugs, however figuring out a way to attach said plate to the head is proving a challenge. I don't want to use the valve cover bolts ideally, and I have found that out of the four hex threaded plugs in the valley, one of them has a small M5? threaded hole in it, but not the others.

Question is - does anyone know the exact part number for this plug? As I'd like to replace the other two with the ones with threaded holes, which would make it a much neater install.

I'm coming up with 90341-24007 off of the EPC, can anyone confirm this would be the right part?

Bear with my picture stolen off the internet:


If you look at the rightmost end, that plug has a threaded hole, the others don't. That's what I'm after.

Alternatively, does anyone know if it's safe to drill and tap these plugs instead, assuming one can't get the ones with the threads already in them?