misfire , bad coil?
#1
02-17-2018, 04:01 PM
misfire , bad coil?
2002 quad with 4.7 started hearing a snapping noise from under the hood. With everything off in truck you hear it driving down the road. Louder when accelerating. I’m thinking it is a bad coil causing a misfire. How can I confirm this? I know all plugs should be replaced due to high mileage on them but can I just replace the faulting one and coil until weather permits changing all?
How owe do I figure out the bad one?
How owe do I figure out the bad one?
#2
02-18-2018, 06:10 AM
You'd need to pull/unplug each coil while idling. The coil (or plug) that poses no change to the idle, would be bad. Obviously if you're going to all that trouble already, you might as well change the plugs. Also, a misfire should be producing a CEL. How many miles on the plugs?
Last edited by Dodgevity; 02-18-2018 at 09:24 AM.