neospazzy

Just purchased a CPO 2017 991.2 Base Manual (with options including PSE and Sports Chrono) with 19K miles on it.

Yesterday during a drive, I noticed a "ka-thunk" noise coming from behind the car when I came to an intersection (0:04). It sounded like something fell off. I proceeded to drive into the shopping center and I heard the muffler putting away as if the engine is misfiring (0:29). A few seconds later, the sound coming from the engine got worse with a now "popping" noise as I proceeded to stop the car (0:44). There were no warning lights on the instrument panel. While parked, I gave it some throttle and it now sounded normal. I turned off the engine and walked around my car and found nothing unusual. Upon restarting the car and driving away, the issue did not come back. Weird!

I uploaded a video of the event from my dashcam. You may need to turn up your volume to hear it.


I scheduled an appointment with the dealership this Friday and I did send a copy of the video to the Porsche service adviser.

Anyone else experienced something similar? Is this an engine that is misfiring? Any insight of what possibly could be the issue could be useful if any of you experienced the same thing.

LexVan

What is your gas situation? Tank low? Bad gas??

It should have thrown some codes. The dealership should be able to read them.

Could be a bad/failing coil pack.

Report back.

Peter80

Yep, likely you have a dodgy ignition coil. Not expensive. When dealership plugs in their kit, it will tell them which cylinder. Apparently they are prone to water damage from underneath car if drive much in the wet.

NJ991

drcollie

Agreed, probably a coil pack. Check engine light eventually will come on if it persists. OBD-2 scanner hookup will show "Misfire Cylinder ___". Than just put in a new coil pack. Your's is under warranty, they could probably do that in 10 minutes once on the lift.

SeeForce

this is easy. its the fetzer valve.

neospazzy

I will mention about the coil packs to the dealership. I also read somewhere that it could also be rocks thrown up into the calipers. I took the car out last night the issue has not come back, but will take it in regardless just in case.

Thanks for all your help guys!