I need helpful advice from experienced Camry 2000 users/mechanics. My car stops accelerating/firing after driving for about 15 minutes. The car would fire normal again after leaving it to cool for several hours. After running for another 15 minutes, the issue will occur again. I did a diagnostic scan on the car and the result pointed to MAF sensor, Air to Fuel Heater sensor and fire plugs. I replaced the MAF sensor, Air to Fuel Heater sensor, plugs, plug wires, fuel pump. But the problem still persisted. I will appreciate any useful idea on what could be the cause of this issue. Thanks in anticipation.