I have a 2004 F-150 5.4 engine, every time I come to a stop are turn hard it cuts off an its hard to start in the morning, I bought a throttle position sensor, throttle acuator, master air flow sensor
5 Answers
Has the vehicle been tuned up since 2004? Take it to a place like autozone and see if any codes have been set. Hard cold starting is usually a sign the vehicle may need a tune-up. When the wheel is turned the power steering pump exerts a load on the engine which could cause misfiring engine to stall. Get an HEI spark tester and test each spark plug wire for "fire". They're only about 15 bucks. You certainly have eliminated a lot of causes by throwing parts at it.
Oj is right, need to know if there are any codes. The evaporative emissions system can also cause a similar set of concerns. If the engine is ingesting fuel vapors at stop or on initial startup it will cause it to stall. I've put a lot of vapor management valves on Fords due to them sticking open intermittently.