Toyota Repair: engine shakes then dies, gasoline octane, toyota camry

Question

I have Toyota Camry 99, 62,200 miles; it has been running good for years. Recently I have problem: When I stop at the red light, the engine stops too. I can restart the engine again only by full throttle. If I restart engine without press the gas pedal to the floor, it doesn't work.
Seeing red light in the front I slow down the car, the car shakes a lot; when I stop then the engine stops, all the warning lights are on. When the car shakes, I change D to N the engine may keep on running. At the next red light, the engine dies again.

I went to a mechanic; he changed the "valve IC control" and told me to use 2 full tank of gasoline octane #91; after that I can go back to #89.  There was some improvement, but the engine still dies after I slow it down.  It does not happen all the times.  I brought the car back to the mechanic, the engine ran ok.  He could not find anything when it is not broken.

Please tell me what I have to check.  It is only my guess that the engine does not get enough fuel during deceleration.  Thanks.

David


Answer
Replacing the IAC valve normally fixes this stalling condition, I suspect that there may be an intake leak, maybe the mechanic forgot to reconnect a hose or electrical connector, I would take it back to the mechanic that replaced the valve and leave the car there until it duplicates the problem.