iammacey

My 981 GT4 was throwing codes due to coil packs under 10k miles. Granted, I have Dundon headers. Replaced coils and plugs, installed heat shields, and cleared codes. All good.

981KMAN

@iammacey Did you install both Upper & Lower Heat Shields or just the Upper?

I think most of the issue is Radiant Heat from the Cat to the Coil, so just the Upper Heat Shield should solve the problem...??? Yet Porsche put the Lower Heat Shield there for some reason in the 911. Maybe uneven heating of the Head Cover? Any ideas?

Thanks.

ICNU

I always wondered the same thing in that why does Porsche use heat shields on the same motor in the 911, but none at all on the 981? But then I got to thinking about the fact that 911 variant motor is flipped 180° around vs the Cayman, so things are very different under there from the exhaust routing, to basic physics of airflow under the car.

Its not an apples to apples comparison between the two models despite the fact they share the same motor. At least that's my take on it, as the Germans are very purposeful typically in their designs, and I doubt they just "forgot" on the 981, and its a cheap part so its not like its a cost saving thing. So if this really is the case, then one has to wonder if we are making things somehow worse by using them? They left them off for reason. It would be great to know what that specific reason was?

Larson E. Rapp

The reason is that automakers will sell their own mothers into slavery to save $1/vehicle, and Porsche is no exception. That's the car biz for ya. The coil packs don't tend to fail within the warranty period, so...

iammacey

I installed upper and lower. Relatively cheap parts and simple enough to install if you can get the car off the ground and the rear wheels off.

Running headers opens up the space a bit and allows more room to work.

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Ernest72

Changed my coils and the PSM warning has gone away.