I have a '04 996 4S Cabrio with manual 6 speed. PCCB package and the X51 package.
I've been reading all the posts around the misfire codes and I've also had the ABS code too. (that's in a different thread)

Bought the car at 43k miles and ran great for about 2k miles.. then I started getting the codes. First it was just the misfires.
So replaced all the plugs and the coils with new. Beru coils (the newer version) and the plugs folks recommended here.

Took care of the misfires for awhile... then I got hit with the ABS code.
Replaced the brake switch (btw... I have never contorted my body as much as I did to get that sucker replaced)
Still getting the code--- car would run great then all of the sudden lose power and the ABS CEL would light up.

More research here and found it could be the MAF. So I replaced that... 3 times must be the charm as I haven't received that code any more.
Also cleaned the throttle body though it wasn't that dirty.

However, I'm still getting intermittent Cyl 1, 2, 6 misfire codes. I clear them and the car is ok for awhile... then it seems to come back after running hard.

I haven't swapped coils and plugs around yet but I'm considering it. I did confirm all the coils are fully seated.

I'm honestly baffled at this point. I know this seems like a duplicate post but need some help. Happy to provide additional details.

Thanks for the help.

David

 

What plugs you running? Check cables for cracks. Had that in another one of my cars. Oil may also be getting past rings. Pull plugs again and check for burns. Dumb point, but pertinent: check gap on plugs. I have had plugs bought new and installed with incorrect gap.

 

I put Bosch OEM 6 Piece Spark Plug Set # 0242245559 / FGR5KQE0 - Porsche OE #: 99917022390 in it.
99760210402KT1KT were the Beru Coils.

I'll check the other things out and reply back with findings. Appreciate the reply.

 

Another thing to check is for is a coolant leak possibly spraying the coils and eventually working it's way to the plugs.