I posted something a while ago about my car jerking sometimes when I shifted. I was looking at another posting about misfiring and it seems that my car is having the same problem. I changed the spark plugs and tha didnt seem to work it still misfires sometimes. I was thinking maybe the ignition coils would be bad or something someone also mentioned bad gas maybe? Valve adjustment?

 

Valve adjust is a good idea and changing your gas is a good idea. Coils ether fail or don't their is very few cases that the coil is a little bad. Start your car up in the dark and see if you can see any spark leaking out of your plug wires. Look at your cap and rotor. Take your plugs back out you can tell what cylinder is misfiring because it will be black and possibly soaked in gas. Maybe check your fuel pressure.

What modification do you have on the car?

 

Just an CAI, also I can't see any spark cause I have ignition coils and wont be able to see anything cause the spark plugs are inside

 

lol i didn't know what year. So I'm guessing you have an obd2 car it should be picking up the misfires and setting a code. Do you have a code? p0300 random miss p0301 miss in 1 p0302 miss in 2 and so on p0303 p0304.

 

If you have a friend with the same model civic you can swap coils and see if that cures the problem. Or if you have a tester on hand you can see what cylinder is misfiring and swap the coil with one from a different cylinder and see if the misfire jumps to that cylinder. If it does then it's a bad coil.

 

check ecu codes

 

Is there some kind of special tool to find these codes?

 

Code reader. You can just go to autozone and they can scan the codes.

Is the CEL on?

 

I know I sound dumb but where do you find that? CEL?

 

the Check Engine Light (CEL) is the one right up by your tach or speedometer on the left side I believe.