Last week I got back from a two week trip and came to turn on my car (95k miles) and I quickly noted a flat. Put the car in park to check it, and all of the sudden the engine is revving–1500rpm up to about 3500rpm and back down, over and over again. Put on my spare and headed to the shop. The whole way there, about four miles or so one-way, the car could hit 40mph without me on the gas. I turned the car on/off about five times, still having the same issue. In total, I drove about 25 miles with this issue, then, all of the sudden it seemed to be solved.
My mechanic seemed troubled by it when he took a look. No one could diagnose the issue, just had the air leak that caused the flat on a Saturday afternoon fixed, but I haven’t taken it back to them because the issue isn’t happening anymore.
This comes on the heels of taking it in and having the fuel relay fixed because of the well-documented issue with this car stalling on start with warm temperatures. That fix was supposed to take care of things, but the issue still persisted following the fix.