P0303 Third cylinder misfire

I didnt want to clog up the plenum removal tutorial with this.

I did the plenum removal and changed the spark plug yesterday, and it ran so much better than before.

Unfortunately after 10 miles the engine light came on and ran a little roughly at idle.

I got it scanned today and it's a P0303 third cylinder misfiring, I can do the plenum thing much quicker now.

Could it be as simple as not having tightened the spark plug enough or not having pushed the spark plug cap down hard enough?

Thanks for any suggestions. :)

what plugs did you put in?

I put the stock NGKs in there.

i would go around and double check everything first. like u said you might have forgot to connect something.

Quote:

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Originally Posted by pinoyesv6

i would go around and double check everything first. like u said you might have forgot to connect something.

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Im starting to think I may have, looking at the picture in the tutorial there is one compnent I dont have. Maybe I tucked it unded the back of the plenum. Dumbass. :D

Any idea what this is Im missing? :

http://i31.photobucket.com/albums/c3...plenum15-1.jpg

Update: The plugs I put in were from the last owner, and now I dont think they were stock as he said. I bought some NGKs and stuck them in a few weeks ago, reconnected the battery and the engine light came on again, although no idling problems.

I was supposed to be going on a road trip but due to the engine light I took my Acura instead. Got back last week, went for a drive in the Galant (first proper drive since spark plug change), engine light still on, BUT, after a few miles it went out and hasn't been a problem since!

Thanks Guys.

Still no idea what that component is, my car must not have it.