Thread: Cylinder 5 misfire trouble code P0305

It helps people like me who currently has the exact same problem and i am currently going through the steps suggested here to try and resolve the problem. Currently i have replaced the plugs and wires but no fix yet. I will try to update what the final solution turns out to be.

I've just had this happen to me yesterday, my car was fine in the morning but running sick as a dog in the afternoon. Flipped the hood and there is oil all over the front of the engine; looks like the valve cover gasket has gone again! Threw the P0305 code cylinder 5 misfire. Have ordered plugs and leads and a replacement coil,( just in case), and I've already got a spare gasket. Is there anything else I should look for, only being in the UK parts take forever to arrive here?

Plugs and leads already on the car look original, so I'm changing those anyway. The car is a 1998 Grand Prix GT. Also threw a code for the Crank Pos Sensor, as the tacho stopped working and the Traction Off light came on.