Weird stalling

My 2002 car (158,000 mi)stalled when idling about 15 times in 2 weeks, and would re-start (sometimes after 3 or 4 tries, sometimes on the first try) and the TCS and SLIP lights would come on, and stay on until I turned the car off. A week ago, it quite stalling and I thought all was well, until driving at 45 mph yesterday it stalled again. I took it to my mechanic who says it is showing no codes and has run fine for him. Any thoughts? I fear being on the highway and having it stall again.

Change the fuel filter and have a fuel pressure test performed to test the system (including the pump).

The TCS (Traction Control System) is a separate issue.

CEL and codes?

will do. The service engine soon light has been off for a week, and no codes came up when the mechanic hooked it up to the computer.