Code P0301 Misfire on Cylinder 1.. Help
 

Hi guys I really need some help here.. I have a 2002 Honda Civic LX and it broke down on me while I was driving it on the freeway and it hasn't started since. After having this checked my buddy came to see that the timing belt was worn and needed to be replaced. We replaced the timing belt and all other belts, also did the water pump and the camshaft position sensor, also replaced the spark plugs.

We tried starting the car and it will start but I have t floor it for it to stay on and the engine is really jumpy,I take my foot off the gas it shuts off. The CEL is flashing and we're getting a P0301 Code for a misfire on cylinder 1. We thought it could be the coil pack so we swapped it with another one from a different plug and same thing. Then we swapped the spark plugs to see if it was that causing the problem and same code...

Please HELP..

Re: Code P0301 Misfire on Cylinder 1.. Help
 

did you get water or something other than fuel into you gas tank? other liquids don't burn like gas so when the engine starts and is running it will misfire.

Re: Code P0301 Misfire on Cylinder 1.. Help
 

what brand spark plugs are you using bosch ???

Re: Code P0301 Misfire on Cylinder 1.. Help
 

No other fluids in the gas tank but gas. The plugs are Autolite plugs that my buddy got at Autozone.

Re: Code P0301 Misfire on Cylinder 1.. Help
 

you shouldn't use anything other then NGK or DENSO in our cars cheap plugs can cause problems.

Re: Code P0301 Misfire on Cylinder 1.. Help
 

OK Im gonna change out the plugs today.. I'll get back to you guys.. Thanks for the help.

Re: Code P0301 Misfire on Cylinder 1.. Help
 

I put in the new NGK plugs and still having the same problem. Car only starts if I floor the gas and the engine is jumping and misfiring. As soon as I take my foot off of the gas the car shuts off. Anybody got any ideas or has anyone ran into this problem?

Re: Code P0301 Misfire on Cylinder 1.. Help
 

Help.. :hammer:

Re: Code P0301 Misfire on Cylinder 1.. Help
 

If i had to say i would same the car jumped time go back in and make sure everything is lined up along with the spark plug wires running from the distributor to the plugs.

Re: Code P0301 Misfire on Cylinder 1.. Help
 

We took everything out and checked the timing and the marks all lined up.. we even turned the crankshaft 2 turns counter clockwise until No.1 cylinder was at TDC of compression stroke with the timing marks aligned, and nothing. Theres no distributor just coils.

Re: Code P0301 Misfire on Cylinder 1.. Help
 

fuel pump work?

Re: Code P0301 Misfire on Cylinder 1.. Help
 

Yeah the fuel pump turns on.. I can hear it when i turn the key. Any other ideas?

Re: Code P0301 Misfire on Cylinder 1.. Help
 

did you do proper engine timing when you changed that belt?

check that the injector clips are not corroded and have a proper connection

Re: Code P0301 Misfire on Cylinder 1.. Help
 

The engine timing is correct we went in and double checked. I'm not sure about the injector clips so that is gonna be what I check next. Anyone else got any other ideas?

Re: Code P0301 Misfire on Cylinder 1.. Help
 

do a compression test. the gauge is super cheap online, $8 on harbor freight

Re: Code P0301 Misfire on Cylinder 1.. Help
 

Check compression as mention ^^ and the plugs, what cause the car to break down in the first place?

Re: Code P0301 Misfire on Cylinder 1.. Help
 

I dont know what caused the car to breakdown.. We're thinking it was the timing belt because it was missing teeth.. but after we changed it the car started misfiring. My first thought was that the timing was off but after double checking the timing we're stumped.

Re: Code P0301 Misfire on Cylinder 1.. Help
 

valve crash maybe?

does it idle at all or die soon after?

Re: Code P0301 Misfire on Cylinder 1.. Help
 

I think you just answered your own question. The belt was missing teeth? So therefore it jumped and bent valves. Do a leak down check to confirm.

Re: Code P0301 Misfire on Cylinder 1.. Help
 

I'm going to have to get my buddy to check the valve.. Thanks for your help.

Re: Code P0301 Misfire on Cylinder 1.. Help
 

The car only runs if I floor the gas pedal.. as soon as I take my foot off of the gas the car turns off.

Re: Code P0301 Misfire on Cylinder 1.. Help
 

any white smoke out the back?

check your air intake, mas and iacv.

can you swap injectors? how many miles on the engine, injectors might need to be replaced or cleaned.


also, if your belt was missing teeth, you might have damaged valves, time to pull the head

Re: Code P0301 Misfire on Cylinder 1.. Help
 

check to make sure you did not plug the map sensor connector into the TPS connecter or vice versa if they are backwards the car will start but only stay going if you floor it and usually die below 4000 rpm

Re: Code P0301 Misfire on Cylinder 1.. Help
 

i agree! i guess in this case a simpler compression check is enough though. i'm surprised the mechanic didn't do one since was highly likely the valves would have gotten bent if the timing was wrong.

Re: Code P0301 Misfire on Cylinder 1.. Help
 

Do you mean the Crank and the Camshaft position sensors? The sensors that are under the cover where the timing chain is?