3rz cylinder 1 misfire

i have a 99 Tacoma 3rz-fe with 200k miles, check engine light came on a few weeks ago it read cylinder 1 misfire, so I changed the plugs plug wires and igniter and it still is misfiring. I can feel the engine shaking when it idols, and I went from getting 25mpgs to 13. Also when I put it in neutral the RPM’s will drop to 400 and come back up to 700. I do not know much about engines but I know it’s only getting worse over time! Any suggestions on what I should do next? I was thinking a compression test!?

 

Could be bad injector #1

 

ILL check into that, but I was just messing around with it and while it was running I disconnected cylinder 1 plug wire and there was no change in the idol

 

That makes sense. If the cylinder is not firing (for whatever reason) disconnecting the plug wire associated with that cylinder should have no effect.

 

Did you ever figure out your issue