rappyf4i

I've got a raptor quad with an f4i engine in it. Can get it to run but runs like **** will rev up a little but then cuts out and won't idle. Its flashing codes 2. 7 and 9 which I looked in book and said map, ect and iat. I've tried new map sensor and check vacuum lines and there not plugged. Has new plugs, spark at all 4, fresh gas, bypassed tip over sensor. Checked timing and is on. Cleaned injectors and tested them and they all work. Anybody else have a prob like this? How do u erase codes from ECU?