After a month out of the country, I returned home tonight and decided to take my Boxster on a nighttime run. I had lots of fun after missing the car for a month, but I noticed a new issue cropped up half an hour into the drive.

I found that the throttle would sometimes suddenly cut out and act as if the pedal is in the idle position. When this happened, the car would behave as if it's at idle no matter how far I push the accelerator pedal. This happened around 4 or 5 times tonight over the course of an hour's driving. It happened most often when accelerating from a stop on an uphill slope. The throttle would start behaving normally again if I released the pedal all the way then pressed it again, or if I pressed the clutch and then released it.

After some searching online, I found a few people reporting similar issues, though not all managed to discover the cause and the causes seemed varied to an extent. One common theme I saw was people reporting flaky brake pedal switches. Several people with 987s and 997s mentioned similar issues going away when they replaced the brake pedal switch.

Have any of you experienced similar behaviour from your accelerator pedal? Do you think the brake switch is the culprit? Any suggestions on what to look for?

Compilation and summary of existing threads on such issues:

https://rennlist.com/forums/997-foru...continues.html
ajaybb had identical misbehaviour, and it appeared to be caused by the steering angle sensor tripping PSM

https://rennlist.com/forums/997-foru...le-sensor.html
CaptSteve123 had also the exact same symptoms, though no solution is stated

https://rennlist.com/forums/997-foru...tle-pedal.html
https://rennlist.com/forums/997-foru...tle-pedal.html
McCulla had a similar issue, but different in the sense that the throttle would start working by itself after a few seconds, whereas I need to release and reapply the throttle. No posted resolution in the thread.

https://rennlist.com/forums/997-foru...at-s-this.html
McCulla managed to fix the issue by replacing the brake switch. andrews7889 had the same issue, and also fixed it by changing the brake switch.

This has happened to me a couple of times. The issue goes away after a couple of seconds. I recall these instances occurring for me after I hit a bump and likely triggering PASM or TC.

I will follow this thread in case it keeps occurring and I can find a resolution.

Thinking that maybe some sensors/switches had become sticky after the car sitting for a month, I did some sort of dance actuating all the pedals repeatedly today before starting the car. I then went out on a 90 minute Sunday cruise with lots of starts and stops.

It seems the behaviour is gone - the accelerator pedal worked consistently without a hitch today. Hopefully it stays this way with regular use.