CEL + Limp Mode = why?

[Mabuhay]

On a long drive from NJ back to Boston, my 2006 Boxster S, without warning, went into "limp mode". The car only has 13k miles on it.

The Check Engine Light (CEL) went on and the car refused to accelerate despite me stepping on the gas. I ended up running along the breakdown lane and took the first exit. The car ran slllowwwwllllyyy...

I parked the car and checked the gas cap. It looked fine to me, but I turned it to make "one click". After waiting a while pondering what to do with my pregnant wife, I tried to start the car and it fired up. It ran normally, but the CEL is still on. We were able to drive back to Boston with no other issues. The CEL stayed on.

I plugged in a "Carchip" and turned the CEL off via the OBD2 hoping that I could take some data points in the event that the CEL would come back on. But it didn't. The car runs as STRONG as always. There are no oil drops of any kind in my garage and the oil level is perfect (not burning or leaking oil).

So the question is, could it be "bad gas" in NJ? Or could it be just that maybe the gas cap needed "one more click" to be tightened?

[wvicary]

It could have been many things to cause what you've described. You need to get the codes read and report then here. A loose gas cap wouldn't have put it into limp home mode.