Q&A

You should have a check engine light on and codes stored in the power train control module. Can you get these codes and post them?

I am a certified ford tech, and this is a common problem in the 5.4l 3v engine, this engine has overhead cam with variable cam timing (vct), it has phasers on each cam to adjust timing to provide more power or better mileage. but usually after 80k or so these phasers stick so at low throttle or high throttle the phasers stick and are basically backwards from what they should be. they are simple to replace but i would not recomend a DIY because there are special tools to hold timing chain and tensioners in place and if you loose where they are at, then you have to pull off the front cover and re-time the entire engine, most likely your warranty is out, so if you want it fixed then better start saving because it does not come cheap (about 15 bills)..........hope i was helpful