2002 ford engine surge then stalls when brakes applied, and when head lights turned on
engine surges then stalls when brakes applied and then head lights turned on ......i
replaced air idle control valve and checked for vacuum leaks
Sounds like you have a bad brake booster. That is what the master brake cylinder is attached to. Booster has a vacuum line going to it that goes to the engine and air is being pushed back to engine when brakes are applied because the brake booster is bad.
Now as far as the head lights being turned on and it happens can not answer that one.
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