997 Engine Cuts Out: Seeking Expert Help for Mystery Issues

Hey there, had exactly the same symptoms on my 2011 Porsche Cayman S last summer. The engine would cut off out of nowhere, rough idle, jerky acceleration, the works. Turned out to be a faulty accelerator pedal module. The sensor inside was acting up, sending wrong signals to the ECU. Got it fixed at my local Porsche specialist. They had to replace the entire pedal module assembly. Not a complex job, but definitely needed someone who knows what they're doing with diagnostic equipment. It was causing the engine to get wrong input, hence the terrible fuel economy you're experiencing. While not a catastrophic issue, it's definitely something you want to get sorted soon. If it fails completely, you could lose throttle response while driving. Worth noting that my symptoms started exactly like yours, and they got progressively worse over a few weeks. Can't stress enough how important it is to get a proper Porsche specialist to look at it. The generic OBD readers at regular shops often miss these specific issues. Hope this helps!

Thanks a lot for sharing your experience! That's really helpful. I'm glad you mentioned it as I was starting to worry it might be something way more serious. Quick question, do you remember roughly how much you ended up paying for the fix? Also, has everything been running smoothly since the repair, or have you noticed any other issues popping up? Thanks again!

Hey again! Just wanted to follow up, I got my Cayman sorted at the mechanic and thought you'd like to know how it turned out. You'll be happy to hear that since getting the accelerator pedal module replaced, the throttle valve error completely disappeared and the car's running like a dream! The whole thing cost me 205€, which honestly wasn't as bad as I was expecting for a Porsche repair. The car's been absolutely perfect since then, no more jerking, no unusual cut-outs, and my fuel consumption is back to normal. It's been about eight months now and I haven't had a single issue pop up. Such a relief! Really glad I could help point you in the right direction with this. Sometimes these Porsches can be a bit finicky, but once you get the right diagnosis, it's usually a straightforward fix. Let me know how yours turns out! Cheers!

Thanks so much for the update! I actually just got back from the mechanic yesterday. You were spot on, it was indeed the accelerator pedal module causing all the trouble. Ended up paying a bit more than you did, around €280, but totally worth it considering how much better the car runs now. The whole experience wasn't nearly as painful as I'd feared. Found a great Porsche specialist thanks to a local car club recommendation. They diagnosed it quickly, had the parts in stock, and got it fixed the same day. No more jerking, no more cutting out, and my fuel consumption has improved dramatically. Really appreciate you sharing your experience, it gave me the confidence to get it sorted before it got worse. The car's running like new again, and I couldn't be happier! Thanks again for all your help!