I had a coil go out on my 2005 Chevy Impala 3.4 liter a month or two back. scanner has said "cylinder 3 misfire" both times.

it went out again yesterday. i put a new one in. this time, the check engine light didnt go off. i unplugged the battery for a couple minutes and it didnt reset the check engine light. i should have left if off longer.

i have a really dumb question... is cylinder 3 in the front of the engine, ( towards the front bumber )

or is cylinder 3 in the rear of the engine ?

the reason i ask... is i had the spark plug wires looped over something to keep them separated. they got bumped, and i wonder if the check engine light is still on, because maybe i crossed the spark plug wires???

thanks for any help in advance.

and BTW, i bought this chevy used for a vehicle to save mileage on my truck 2 years ago.
i just bought a 2011 Ford F350 crew cab / long box / 6.7 liter diesel. 400HP and 800Ft Lbs of torque

Pretty sure you need to reset the computer with a scan tool....unplugging the battery doesn't work

The spark plug wire could be broken too. As a rule if I change any part in the ignition, I change them all... the plug it self could be fouled too.

#3 is the middle cylinder on the back side.#3 and #6 share a coil.#6 would be on the front right.1,3,5 on the back,and 2,4,6 on the front,laft to right.

A bad spark plug wire can burn out the coils-have you replaced the plugs and wires?

Cylinder 3 should be on the back of the engine.  Sometimes they are numbered on the coils or near the coils.  If it's still misfiring, it might not have been a bad coil.  It could also be a spark plug or fuel injector.

ETA:  the front is 2, 4, 6 and the side nearest the firewall is 1,3,5 the coils as you look at them from passenger to drivers side(passenger side being the right) 5,2 /3,6 /4,1

thanks guys

i should have mentioned that i replaced the plugs and wires this easter.

if it were an injector, are those tough to replace on these cars?

I have a 2002  Chevy with a 4.3,
from what I have noticed - when I fix what ever mad the light come on, the engine light will clear itself after 10 or so start-ups with no error.

You do need to clear the code, just unplugging the battery will not clear it.

The light going out doesn't mean the code is cleared....but yes the light may go out after a while

Advanced auto will clear the code for free if they have the tool .....Most larger hubs handling commercial accounts have scan tools handy

My wife's van has the same motor and had a cylinder misfire last year according to my F.I.L who put on it his computer. It was a loose plug wire.

Depends on your ability.  It can be a DIY project if you have the tools and time.

well here we go again.

this morning i jump in the car and head off down the road. driving fine. then out of nowhere on the highway it starts "stuttering"

like a misfire in the cylinder. but not very loud or anything you could just feel it in the gas pedal / through the vehicle. then it stopped. then a few miles later it did it again, off and on. i was halfway done with my errands and had to finish them. it really didnt do it *much* after that. drove it for another half hour.

so i put some STP fuel injector cleaner in it. i put the original spark plug wires in the trunk. maybe it if starts doing it again ill put the original #3 wire back on to see if the NEW wire was junk.

a new injector is $95 + tax so i dont think i should just pop one in to try it out.

any other ideas?  that latest coil only lasted a week or less.

and where the hell did they hide the injectors !?!?!?!?!?!?!

UPDATE-

found a small crack in the #3 plug wire. replaced the rear 3 wires and she runs like a top again.

thanks for all the help.