Hi ,
My Honda fit 2009 misfires even after I changed all sparkplugs and coilpacks ( coilpacks are after market ) , it's number 2 and 3 and if I swap the sparks and coilpacks with 1 and 4 which are good still number 2 and 3 misfire . I know it's not spark and coilpacks . What do u think is the problem and How much ( roughly ) to fix them ?
Thanks
Here's the thing. Misfire is kind of a misnomer. It doesn't mean that the spark plugs aren't firing correctly necessarily. Many problems can cause that. For example, if the fuel injectors are bad on those two cylinders that will cause him his fire. Or if pistons valves piston rings are worn in those cylinders that will cause them misfire. Also, if there's a computer failure sending impulses to either the fuel injectors or the ignition coils on those cylinders incorrectly that will cause a misfire. Many things can cause a misfire so start by doing a wet and dry compression test of the engine to see if it's in turn those the engine first
Get it scanned for codes. Sounds fuel related, ie, fuel filter, pump, clogged injectors, etc.
Try switching the #3 injector with a non-missfiring cylinder to see if the misfire moves with it. If it does, you know the injector is bad or clogged. Same with #2. Also, make sure the connections to the injectors are free from corrosion and tight.