Car misfire once or twice a week
 

My 07 Fit misfires maybe once or twice a week randomly, but only while stopped at red lights. It will misfire once and then not again for a week or so. I'm not too concerned but I'm curious as to what is going on and why it only misfires on occasion while stopped.

Ignition coils! Had EXACTLY same things on my Fit

Bear in mind that a weak spark will not 'set' any CEL codes. But it still results in a poor spark, and incomplete combustion, which you might not notice from the driver's seat.


The Holy Trinity of Fit misfire remedies:


1. Replace sparkplugs (new Iridiums)
2. Replace coils all at once (Hitachi part # ending in 053)
3. Adjust valve clearances (loose end of spec on exhausts)