What are you referring to as "pressure kits"? Normally with a misfire you start by doing testing. In this case I would start by erasing the code, then swap the coil from cylinder 3 with the one from cylinder 1, then while doing that I would swap the spark plugs between 2 and 3. Now start it and see if the misfire moved. Say it now reads as a misfire in cylinder 1, replace that coil. A misfire in cylinder 2 would have me changing all 4 plugs. Now say you swap the plugs and it's still missing on cylinder 3 it could be an injector. Or it could be a mechanical problem. To determine which you could do a compression test.
https://www.2carpros.com/articles/how-to-test-engine-compression
If you do that and you see each cylinder showing close to the same numbers, it isn't likely to be a valve or mechanical problem, instead it's likely the injector. Now being a Honda, you really want to use OE parts to repair it, Honda and Toyota both are fussy about parts. Then you want the injectors to be balanced so replacing all 4 usually gets you that. It's more expensive but you get a better repair. As to how soon, ASAP, a misfire will dump raw fuel into the exhaust system and that can destroy the catalytic converter in a very short time. I've seen them fail within a few days if there is enough fuel. Then you end up replacing it as well. On your car that is a $1,700.00 part so you want to avoid that.
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Friday, June 6th, 2025 AT 2:54 PM