I have an 09 997.2 C2S
23k.
Every morning for the first 30-45 seconds my car stutters, it never misfires, never throws a code.
Always happens, no difference summer or winter.
Does not do it but the first time the car is started. I once drive within a weekend 1000 miles, 2 x 500 miles, the 3rd day did not do it (I think)
Got to service, no codes, mechanic drove in car with me, felt it.
Said, could be coils, unlikely to be sparks at this age. We can run the fuel injector cleaner and see.
I always tank 93 octane. Any decent looking gas station.
Any thoughts?

 

Ignition = coils = plugs would get my attention first.

 

30-45 seconds,,, I d say there s nothing wrong.. My 09 idles different when first starting for a while, but I wouldn t call it stuttering. I d have to agree with plugs first if anything. I d like to see those plugs if you change them at 23K. With my exhaust tips always black on these DFI engines it makes me wonder how long the plugs will be good.

 

My 2012 GTS sometimes stutters very briefly on cold startup only. I recently learned that, on DFI cars, the DME is programmed to run rich at cold startup, with the exhaust valves not completely closing during combustion. Porsche's intention with this arrangement is to heat the cats as quickly as possible by sending a hot blast to the exhaust manifold (and, in consequence, the catalytic converters). This is also why black "specks" may appear around the exhaust tips and on the body close to the exhaust - products of incomplete, rich combutsion. Things revert to normal operation pretty quickly after startup.

I can't say whether this is the source of the stutter, but it might be.