I just changed my plugs and wires today. The Service Engine Soon light is off. I am not a mechanic and honestly, I don't think you have to be one. It is not complicated, but it is difficult. I did go ahead and change my ignition rotor and distributor cap. I am glad I gave this a shot, but I probably wouldn't try it again. It is now vibrating quite a bit and I need to figure this one out. I hope this helps you...
It means that more than one cylinder has a misfire history. PO301 would be cylinder number 1 misfire. PO302 would be number 3 cylinder misfire.
It could.
A Grand Caravan would have a six cylinder.
If you have a "check engine" light on, start with having the codes read. A misfire code can tell you which cylinder or cylinders are having problems. A misfire could be the cause of your engine vibration.
Bad plugs, wire , or coil pack.
Bad plug? Bad wire? Bad piston or valve (do a compression test)
sounds like a cylinder misfire..check spark plugs and wires..usually a code will show which cylinder it is, should replace all though
Most likely a bad coil (each cylinder has one) located at the top of each spark plug
Most likely a bad ignition oil. Each cylinder has its own coil mounted at the top of the spark plug
I talked to mechanic and he fixed 5th cylinder misfire on Dodge engine by changing chank shaft postition sensor. It came out on code reader though.
Usually a bad coil , or plug. if the injector was bad , the computer would have coded for it. But the cylinder 3 coil and plug arent that easy to get to. Its the one at the fire wall
P0303 is cylinder #3 misfire. P0300 would be random misfire. Either way you need to diagnose the case of a misfire. Check spark plugs, plug wires(if equipped), cylinder compression, fuel inectors, and wiring.