Multi cylinder misfire


New Member
I drive a 2002 civic ex 1.7L standard trans.
It starts and doesn’t ever stall out, doesn’t even shake bad. However, It currently can barely generate enough power to drive up a steep hill and it is quite loud. It needs a new exhaust, but I mean it is even a bit louder on top of that now. I was getting misfire codes for each cylinder (P0301-P0304) plus P0300 (multiple misfire or something like that). Also the engine doesn’t turn off when I turn the ignition off, until I either stall it or step on the brake pedal. I assume the two to be related, but don’t know for sure.
I checked the coil packs and replaced the spark plugs, I repaired a hole in the intake manifold. It is running better and misfiring less, but the fact that it is all 4 cylinders makes me think it is gonna be something bigger than that. I reset the codes after I changed the plugs today and gonna go back to auto zone tomorrow and see if it is still all 4, I suspect it will be.
I should add that the engine light has been on for some time, and there have been misfire codes for some time, the light just started blinking a few days ago.
I am way out of my league at this point, and am way too broke to go to a mechanic. Please send me any relevant advice, or let me know if you have dealt with this issue in the past.
Thank you!
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