04 S Coils/Plugs Problem FYI

[mudman2]

Loren FYI if you are not already aware there are bad sets of coils out there on 04 S models. The resulting misfire does not show up in PIWIS error logs but does get recorded in the engine log as a misfire incident.

Hairline cracks on the coil body and possible premature wear on the plugs are the cause.

Mine are being flown in as we speak but based on my dealers comments, demand is outstripping supply.

Symptoms are 1500-2000 rpms, 35-50mph under cruise condition, slight gas engine starts to misfire/stutter. keep applying gas and revs pick up and the problem goes away, sounds like fuel to start with but is electrical stress.

Mike

[mudman2]

OK all done here are the parts used

8 * 999-170-218-90 Spark Plugs

8 * 948-602-104-01 Pencil Coil

PIWIS shows nothing visual inspection required

03350050 On Board Diagnostic

22 0.20

[gchu]

Mike,

My CS had the CEL came on last month and the dealer found a record of misfire but not able to see the cause. Only the dealer did was reset it and the CEL did not come back. My CS is 05 but and the hesitation is similar to what you descripted. Do you know the hesitation would be caused by the misfire?

[mudman2]

Mike,

My CS had the CEL came on last month and the dealer found a record of misfire but not able to see the cause. Only the dealer did was reset it and the CEL did not come back. My CS is 05 but and the hesitation is similar to what you descripted. Do you know the hesitation would be caused by the misfire?

Not "the" hestation but a stutter like 2 cylinders not firing at all for short periods. Now if you get both at the same time, thats interesting :( it happened to me once. :censored:

They have to disassemble to see the cracks.

Edited March 3, 2006 by mudman2

[wingless]

Inspection of the driver's side plugs / coils is straightforward as opposed to the passenger's side where extra stuff needs to come off. It should be part of the periodic maintenance / inspection.

[gchu]

Not "the" hestation but a stutter like 2 cylinders not firing at all for short periods. Now if you get both at the same time, thats interesting :( it happened to me once. :censored:

They have to disassemble to see the cracks.

I don't know is it the same hastation as everyone talks about. When it happened, it felt like lost power when try to accerate while at cruising speed, specially when lane changing.

[mudman2]

No George this is a very pronounced misfire which you can feel and hear.

[gchu]

My CEL came up again yesterday. I'll bring it to Carlsen Porsche tomorrow and see what will they find out.