Potential Electrical Problem?
 

Recently, and now more frequently, my 1998 Boxster has been acting like it will cut off completely while driving, but immediately come back on. Like a power flicker. When this happens, the door locks won't unlock or lock, and when I get out of the car, the door doesn't close. Sometimes it helps if I lower the windows, but when I'm in the parking garage at work, I don't feel safe leaving the windows down. I've read several posts about ignition switches and grounds under the seats, but I don't want to poke around too much until I can figure out the problem.

I had the electrical component of the ignition switch replaced several years. The car has done this in past but it was less frequent, and only while being stopped. Now it's doing this while I'm driving (usually in stop and go city traffic).

Any thoughts or advice?

That’s frustrating!
Start with the basics and things you can easily check. Your battery connections, both positive and negative at the battery and where the other and if your negative battery cable attaches to the body are easy to check. There is also an additional connection at the front of the engine that you can get to by removing your engine cover. It’s located at the top of the engine, center, close to the rollbars.
Next, I would pull the driver seat and check my connections to the immobilizer.

Although it does sound like you have an electrical problem, I also wonder if a fuel pump relay or crank position sensor could be bailing. I’m sure others will have thoughts.

Thank you! I will try checking the battery connections first. Hopefully that will be the fix.

Also... check your battery voltage. I've read upon this forum that even minute voltage variations can cause havoc on electrical components. Might need a new battery.

Take it to Autozone... Reilly... wherever... have them check the battery voltage AND the alternator output.

Cheers!

Excellent! The voltage regulators on our car can cause problems as weird as the ignition switch. Mine never through a code, nor cause the car to quit but did hiccup a few times and cause other strange behavior. I remember checking the voltage and seeing 17+ volts! $50 and all good!

17V! Hmmmmm.

So... you replaced the VR... $50... and all is good today?

Yes, This was back in 2013 and I kept the car until last summer. Pull the alternator, replace with a Bosch regulator and reinstall. Car had about 105K on it at the time.

Sounds like there is an electric cut off somewhere.

Check also for a ground problem. Sometimes the ground cable at the alternator comes loose.