I have a 2002 Pontiac gtp supercharged. It won't stay running. The diagnostic code showed P 0305 misfire on cylinder 5. What does this mean and how can I fix it?

Answer 1

When a cylinder has a misfire, it is due to the fuel and air not igniting properly in the combustion chamber, specifically, cylinder 5 in this instance. Typically on GTPs this is due to either a fouled spark plug, or a failed ignition control module or coil pack. Something a little more uncommon is a broken spark plug wire. The first thing to do is perform a tune-up, including new spark plugs, wires, and PCV valve. Next would be to switch two of the coil packs temporarily, and see then if cylinde 5 fires. If it does, then the issue lies in the coil pack or ignition control module, and no further than that. If you or someone you know is familiar with DMMs (digital multimeters), you should check the continuity of the coil packs and the ignition control module. Worst case scenario is to have an automotive technician familiar with or certified in electronics look at the vehicle. Chances are that it will lie in the spark plug or ignition control module. Hope this helps!