Honda b18 CEL on and revs bounce?

I was in the middle of changing my fan switch when Autozone gave me the wrong one. I broke the original I had during the process and decided to just put it back in with the plastic broken, add some radiator fluid, and call it a day. When I turned the car on it took a few seconds, and after it started the CEL light is on and the revs bounce by about 300? What's the issue?

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