P0300 and P0304
 

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.

Currently in the same situation; had it flatbedded home. I'm getting coilpacks delivered next week. I want to follow your situation.

I saw your post when I searched and was hoping that you had a happy ending you could share.

I was thinking of ordering coil packs too. I have too many things going on this weekend, so I won't be able to repair it for a week. Where did you find the best price?

Suncoast seems reasonable; $300ish. Let's hope its simple. I was thinking of snagging o2 sensors too, but maybe after this install.

You could always swap the coil pack from one to the affected cylinder 4 unplug your battery for a few minutes and then retry and see if you get the same code, if it is for cylinder 4 then not coil pack, if same code on the cylinder you swapped to then it is a bad coil pack.

Only takes a few minutes to swap out.

I threw the same type code, luckily I had already planned on my maintenance (plugs, tubes, oil and brakes) prior so had all parts on hand and the coil pack was fine, was a bad plug.

Also could always check the snap (wire) connection to the coiled pack to make sure it is fully connected.

Good luck.

Thanks for the replies.

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.

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.

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.