need help with my jeep 2002 grand

Question

engine code p0305 came up. I changed all the spark plugs and the # 5 coil. Light camu up again. took it in to jeep.The cleaned out some carbon build up. it ran ok for a day now the light is on. Early morning start up has hesitation then it goes away .Any ideas

Answer 1

HI there,

I would do a leak down test on cylinder #5 to make sure there isn't a small head gasket leak allowing coolant into the cylinder. Also, try swapping the #5 injector with the one next to it and see if the misfire moves. If it goes to the cylinder you put the injector on, then you know the injector is the issue and needs to be replaced.