Hello everyone.

I'm having some trouble with my '04 TSX and was hoping that someone would have a clue to what's going on with it. Yesterday, on the way to a friend's house, the car started running rough all on its own while I was driving. At the same time the engine light started flashing and still is flashing. I plugged in my OBD-II reader and out came the following P codes:
P0300 (random miss-firing)
P0302 (cylinder 2 miss-firing)
P0303 (cylinder 3 miss-firing)
P0304 (cylinder 4 miss-firing)

I thought cylinder 1 (P0301) was spared but it's there in the pending codes list as well. So I figured that maybe the spark plugs needed replacing since the car was used and I doubt they've been changed in a long time and thus I changed out the spark plugs. No change. I'm not sure what to do next really. The coil packs themselves seem to be ok but there is something definitely wrong and the miss-firing is very noticeable and clearly felt/heard. I only put in 93 octane fuel since I've had it, though I bought it used. I've also added a gas "detergent" but that would not take effect for a while anyways.

What else should I look for or what can I do? Should I try SeaFoam? I'm no mechanic but I like to try the whole mechanics thing on my own vehicles so I'd like to exhaust my options before I head out and take it to the dealership for diagnostics and fixing. Any questions about something I may have left out feel free to ask. Thanks.

 

My guess is that this problem is beyond the shade tree mechanic stage. I'd have it tended to before you damage something, including the engine.

 

Yeah...that's what I was thinking today after realizing that I've done all I could as a non-mechanic. Will swing it by the dealership tomorrow so they can rip...erm let me know what's the damage.

 

Checking back in...forgot to when I had this checked and fixed.

Apparently my coil-pack-testing skills obviously suck because that's what the problem was. Dealership replaced the coil pack for cylinder 3 and all was well after that.

 

Lucky for you it wasn't something serious.

 

Part number 30520-PNC-004 COIL ASSY.?