Engine dies while driving on 1998 Toyota Avalon

While driving, the engine dies which results in steering and brake loss. There is no stalling and no warning when it happens. Two dealerships and an independent mechanic have tried to diagnose the problem for a few weeks without success, driving the car for 75 miles in the process. Weather and terrain are not issues. The car runs great otherwise and there is no computer evidence of a problem.

Asked by for the 1998 Toyota Avalon
Very difficult to diagnose intermittent problems till is failing during inspection. If dies light shut off a light switch then suspect the ignition circuits. If sputters when dies then suspect fuel delivery problems. Sometimes out of frustration parts are thrown at the problem and sometimes you get lucky. Did you check at repairpal homepage for experts info about your car? There may be a pattern failuer related to this problem. Good luck.
Thanks for your response. Lights, radio, everything stays on except the engine. No sputtering, no check engine light, just a slow decline in acceleration, then steering and brakes go. It usually takes about 5 minutes to start again and runs great ..... until the next episode. Episodes are infrequent - usually about once a month. Most recently it happened twice in two weeks. Initially it was thought to be a key chip/ignition problem. A new key was made and the ignition coil replaced by dealer #1 - the day after I picked up the car it happened again. This has been ongoing for 5 months now. Though infrequent, definitely a dangerous situation. I will check into the homepage for experts info.