I was in the middle of a left-hand turn and the car turned off. The car was hard to steer is how I discovered and I had to coast to the curb. Very dangerous as other cars were turning and I was trying to gain control of the car. I have taken the car to the mechanic several times when it acted as if it was losing power at times when trying to accelerate, but never stopped while I was in drive. All I hear is wait until the check engine light comes on. No one will diagnose...dealer or mechanic as a result. Something is very wrong. Told to just drive it!