Timing belt broke crushed couple valves fixed everything n when i start it up it runs rough n check engine light flashes n if u let all way off throttle it dies
You didn’t fix everything if the check engine is flashing. There are error codes stored, you need to read them and post them here if you want help.
A flashing Check Engine light indicates a major misfire is occurring.
Something was missed during reassembly of the engine.
So you repaired all of the mechanical damage–had the cylinder head resurfaced and reconditioned with new valves and valve stem seals, valve seats re-ground and vacuum/pressure tested, cleaned up any nicks on the piston crowns, checked for cylinder bore damage, and reassembled the engine correctly using a new head gasket and bolts? Did you install a new timing belt kit, and double-check that the timing marks lined up after rotating the engine by hand for several revolutions? Did you double-check that all wiring harnesses have been plugged in tightly–including sensors, fuel injectors, etc?