your mass air flow sensor is damaged. You need to purchase a new one. It cost $200 - 300 online. You can install it yourself. Takes 5 minutes. Don't go to a mechanic, they will rob you saying it took hours to fix, very simple problem. The mass air flow sensor is connected to the coolent, in front of the engine. Look for it. I had the exact problem, took 3 weeks for the mechanic to figured it out. If you keep driving with the damaged mass air flow sensor, it will damage your oxygen sensor and a few other sensors thus costing you alot of money those fix those. Hope i was of help.