I was going reading through this thread and I thought I saw a solution but I will post up my problem ..dont scold me if I duplicate.
I have a 2006 Mercury Mountaineer V6 AWD. The problem I'm having is when I'm driving -- over 50 mph I hear like air rushing or being sucked into something.. it is coming from under the hood. If stop on a hill and then try to start moving again it takes a looooong time to climb the hill, feels like it is struggling and does not have much power. I took it to the mechanic and some work was done on it... it was working fine now the problem is back again. Also when the problem was fixed the gas pedal was tight - I had to apply a descent amount of pressure on the pedal. When I pressed on the pedal the car would fly up hills even if I stopped and then accelerated from a stopped position on the hill. When the car was without the hissing sound driving on leveled roads highways and city was great. I was able to feel the power. This was great but short lived. With the problem back the gas pedal does not feel tight... by that I mean I press the gas pedal and it goes almost to the floor.
Also the engine light would come on when I accelerate fast and hard or if im going up a hill at a fast speed. The light would stay on for two to three days and go out. If I accelerate up a hill or drive on highway for a long way the engine light would come. Then three days later it would go out.....and this keeps on repeating..
I had Autozone check the codes for me... one time it was a
P0193 Fuel Rail Pressure Sensor Circuit High Input
Another time the code generated was for a faulty oxygen sensor.
Then yet another time I took it to a mechanic and he said the code generated meant i needed a new Throttle Body.... So i'm hesitant to throw money and it could be something simple....
Anyone has any ideas??
I noticed someone mentioned the Vaccum Check Valve could that cause an issue like that? And if so would any generic Vaccum Check Valve work or should I try for MotorCraft?
I just starting to read and learn about cars so forgive my car ignorance.....
Thanks in advance!!