2003 mustang cylinder 2 misfire. I changed the spark plugs and wires. Its still have code p0302. What should I do next?

This problem is caused by the EGR valve opening! Ford's better idea was to use runners (tunnels) to carry exhaust gas to cylinders.Over time gunk builds up in these runners and it clogs up.Any cylinder who's runner is open the most will get the most exhaust gas which will kill the performance of that cylinder and will cause it to skip. To prove this drive the car until it starts to skip. stop and unplug the EGR valve wire and start driving again. You will notice the skipping has stopped and the check engine light is on. Stop plug wire back in and get some sea foam and hook hose to intake vaccumn port.This will cause car to smoke greatly but will soon stop smoking. If this doesn't help the carbon gunk has built up too much and the intake will have to be removed and cleaned at a performance shop.

A code P0302 may mean that one or more of the following has happened:
Faulty spark plug or wire
Faulty coil (pack)
Faulty oxygen sensor(s)
Faulty fuel injector
Burned exhaust valve
Faulty catalytic converter(s)
Running out of fuel
Poor compression
Defective computer

Possible Solutions:
* If there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.
* If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.

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