This is a long story and I realize there is a lot of "shoulda dones" that's can be said, but I'm really wanting to know what is going on and what the next step is. I'm pretty broke with one car supporting two jobs and a little kid so cost is a huge consideration... Along with being young and stupid.

So last summer, my 2007 fit sport did the whole coil pack thing and I opted to replace three of the four and plugs. Afterwards I drove around with a cel on steady and codes p0301 and a o2 code for about nine months without any real noticeable performance problems. I could tell it wasn't perfect, but no acceleration issues, mpg was down but not terrible sounded kind of grumblier and less electronic, if that makes sense.

A couple weeks ago cel flashes, noticeable decrease in acceleration power, rough idle, clearly missing. My fist step is to replace that last coil, no change. Codes read for cat and p0301, p0304 and o2 sensor. Replaced cat, now only reads misfire codes (mechanic said o2 was good...) so then I swap the coils and the misfire is now in 2 and 3 and random (swapped 1-2 and 3-4, and I assumed random because I confused the computer) which led me to replace all four coils.

Currently, car only reads p0301 with flashing cel. Has noticeable misfire and vibration pretty much all the time but worst when accelerating, still big improvement since replacing coils. Power greatly improved, back to pre-broken cat days, gas usage still high but not as bad, noticeable fuel smell from exhaust. Vibrations better but still not good.

So now I'm trying to figure out the most cost effective way of going about this since I have no money and every diagnostic is like $100. I'm trying to find the next best step to take.

I think it's unlikely to be the spark system, although it's weird that after all new coils the misfire traveled to a new cylinder... Right?

I'm not thinking vacuum leak because there is only one cylinder affected, wouldn't something like maf or a leak cause problems throughout?

Fuel injector? Dirty or clogged or just done for? I've got some cleaner to run through in the morning. But why would it suddenly be a problem right after swapping coils?

Please say it's not most likely to be a burnt or broken valve. I've thought about maybe a sticky valve or something but the thought of a valve problem is giving me panic attacks.

There's no way this severe of a misfire could be something fixable with a $20 fuel additive is there? Sigh. Bad coil out of the box? That would be best case for me...

Edited to add that spark plugs were fully replaced when I put in all new coils.

 

I read in a thread on Fitfreak that someone fixed his hesitating fir by fixing his EGR valve. I think he actually just cleaned it and didn't even replace it. It can get clogged up with carbon on think. I think is saw the post in the 2nd gen forum. Good luck.

 

So the current issue is a PO301 code?

Just simply swap the 1st cylinder coil with the second (or third, or forth) one and see if the code goes from P0301 to P0302 (depending what you swap it with). If that happens then the coil pack is bad.

If it still gives cylinder 1 misfire with a swapped coil, then we can narrow it down to that one cylinder. Possible issues could be a dirty fuel injector or bad spark plug.

Do it yourself. It's really simple to swap the coils over. It's a free diagnosis lol!

 

When I went to the parts store to swap out the coils to see if it was indeed a bad coil, I had them read the codes first to see if any new ones showed up since yesterday. There is no longer a p0301 and only a p0302. The only thing I've done is added techron according to the directions on the bottle. The girl who pulled the codes for me said she hadn't seen anything happen like that before and she thought it was odd.

Any ideas, I didn't move any coils, should I still try that and see what happens?

I tried the holding paper to your exhaust to see if it gets sucked back at all and it doesn't which I took as a good sign.

 

The battery died on me today. When I put a new one in I had them test the charging system just to rule that out and it was fine, they said. Also had them read the codes again and still a p0302. I guess tomorrow ill try moving the coils just to rule that out for sure.

 

Have you already done the valve adjustment? I'd do that next if the swap doesn't solve it.

 

I vote for a plug problem or a bad spark plug/coil, wire or ECU missed signal. Just becasuse you replsce something doesn't mean its 'fixed'.
And yes it could be an injector with somthing partially clogging the injector flow or even a bad injector. They do wear out. Have you tried swapping the injector on 1?
Surely you didn't mis wire the coil wires. The fact that you smell gas in the exhaust says some cylinder isn't sparking and of course thats poor mpg.