so I have a 06 f150 with a 5.4 it has a really rough idle. its throwing a p0012 and a p0016 code. if I rev the engine to 4000 rpm and back off, the rough idle goes away for about 50 miles then comes back. if I disconnect the battery for 5 minutes and re connect it, it goes away and runs fine for about 50 miles. sometimes I can just go outside and start it and it runs fine all day but then comes back the next day. I replaced both cam sensors and both vct solenoids. any help is appreciated. thanks


another thing. its not knocking or ticking or anything out of the ordinary

 

Next thing to look at is the crank position sensor.

 

My crank sensor went out and just would'nt start. No warnings, codes or prior indications. They are cheap though ($20), so maybe for piece of mind. Good luck

 

I always heard that if your crank sensor went out it wouldnt start at all?

 

The codes don't necessarily tell you that you have a bad part, but they do tell you what circuit has issues. It is just as likely to be a wiring problem as it is a failed sensor.