P0300 And P0304

[KevinH90]

I have a 2000 Boxster with a 2.7 liter engine. I was leaving my neighborhood this morning and my CEL flashed 4 or 5 times and then stayed solid. I drove it home immediately.

I have a Durametric and the codes are:

P0300: Porsche fault code 62 - misfire damaging to cat converter

P0304: Porsche fault code 66 - Cylinder 4 misfire damaging to cat converter

I changed the spark plugs at 30,000 miles when I bought the car and now have almost 56,000 on the car. The spark plug change interval on the 2000 model year cars is 30,000 miles.

Based on some other posts, the problem could be a coil pack. Does anyone have suggestions for repair?

The CEL isn't flashing, but based on the description of the code, I would have it flat-bedded to a shop if I can't repair it myself. __________________

[Loren]

P0304 Misfire, Cylinder 4, Damaging to Catalytic Converter

Best check cylinder 4 for a cracked coil pack, loose coil wire or damaged spark plug.

[KevinH90]

Thanks for the reply.

About 6 weeks ago I ran over a blue plastic tarp. It got trapped under the car on the passenger side. I stopped the car and pulled the tarp out. Some of it melted on the exhaust pipe. I wonder if some of it might have melted onto a coil pack or a plug wire. I'll check tonight when I get home. It is a beautiful day here and I would be driving the Boxster if it wasn't out of action. I feel like I've been cheated.

[KevinH90]

I changed the coil pack on cylinder #4 and cleared the fault codes. I took the car for a 5-mile drive and it is running smoothly with no sign of a misfire and no CEL. I'm going out for a longer drive in about an hour, so that should be the real test.

There was no sign of a crack or other damage to the coil pack I replaced.

Interestingly, the part number for the new coil pack is 997 602 107 00. The coil pack I replaced was 996 602 100 021. Both were manufactured by Beru.

Loren - Thanks for the input on the possible cause of the problem.