I swapped out a seized ICV today, it was so badly corroded that no amount of carb cleaner could free it up. I decided, maybe with a bunch more elbow grease I could maybe eventually get it to come good, but I think it would jam back up again pretty quickly so instead I thought I'd destructively tear it down to see how it's built and whether there might be a way to rebuild them.

Short answer: maybe, with significant difficulty.

I started by grinding off the stakes on the back:

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Once these are out, the plastic end cap has to be pulled straight out. I couldn't get mine to do that (and I wasn't sure how it was supposed to come out anyway) so I ended up using pliers to twist it back and forth until it came free. Having now seen how it works, some WD40 probably would have been a good idea.

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The plastic cap has two pins that slot into the sockets here. There's a clockspring, I think it was pinned to the underside of the back cap, but not sure exactly. I think this is acting as the return spring for the valve, where it fails in that slightly open state that gives you a high idle.

The E-clip comes out to release the clockspring assembly, and now you have this weird Jatz-like plate. This plate is actually staked into position, on the outside of the ICV you will see four pin punch marks in small rectangular recesses in the casting, and those are holding this plate in position. I think you could get this out non-destructively, but you'd need to figure out some way to tug pretty hard on it.

I chose destruction, and used a hack saw to cut the body around the staked area.

This revealed the plate and its 3 T8 Torx screws were holding the coil in place.

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And here we have the rest of the components, which all slide out once the coil assembly is out of the way.

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Note the difficult to see, very rusty and bespoke washer (2nd part from left)

So, could you rebuild this?

It would be challenging, but I think it's doable.

You'd need a way to anchor the plastic end cap/connector once you've destroyed the stakes in the casting. But looking at it, I think you could drill and tap some small screws from the sides to hold it. As long as you're not interfering with the o-ring it should be fine.

The next challenge would be removing the coil back plate, which is staked into place around the housing, and not really feasible to do anything about the stakes. Fortunately, it seems like it's not held in that tightly, and if you had some strong picks or other ways to get hold of the plate securely, you could probably pull it out (don't unscrew the T8 screws or you'll probably damage the coil as you remove it).

Beyond that, it's all just mechanical, and most likely your problem was in the valve housing and all of this was just to get you access to the housing!

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