My 93 Camry (2.2 Litre 4 cyl 5SFE engine) had 220,000 miles on it when the problem started... stalling at stoplights sometimes sputtering at highway speed. First I replaced the ancient platinum spark plugs (of course!). No effect. Then, before getting into the maze of EGR and manifold vacuum devices and tubes, I took a real close look at the distributor. Turns out the 12 volt supply to the ignition coil (this coil is inside the distributor) was intermittently shorting to ground through the distributor housing insulator (black plastic). The faint white discoloration from arcing was a dead giveaway. I guess the insulator and coil just got over-baked after so many miles and then began shorting to the dist housing. No amount of cleaning of the insulator and housing would help. A NEW DISTRIBUTOR, which included a new coil (purchased online for about $128) solved the problem. I'm now at 261,000 miles, and no recurrance.