tripod007

I'm having misfire codes with my 03 civic ex. I first got these codes last year and the problem turned out to be a clogged intake manifold. After I had it cleaned out the codes went away for about 7 months. Now I'm getting these codes again, but only when my gas tank is below a 1/4 tank. Once I fill up the tank and drive it for about a mile the codes go away. Anyone have any explanation for this??

Star1967

Dirt and debri in the tank. Dirty gas and poor quality is a factor. Have you tried cleaning the tank?

Mad Dog Tannen

When did you change your fuel filter last? I am not sure if that is related, but it is often overlooked during tune ups and it can cause issues with idle, startup and throttle response. IF it has not been changed in a long time it probably needs it anyway. considering that you let the air cleaner go that long...

ezone

If it's a random misfire code, I might guess the strainer on the inlet to the pump may be clogged, causing it to cavitate and pull air when fuel level is low.

Or is it a single cylinder misfire code?