For a while now, my 02 explorer xlt has been making what I compare to a spark knock upon acceleration and the engine light has now come on. I had the code read, and it indicated an egr valve, or pfe sensor. There is also a kind of rattle sound when the engine is simply idling. What is odd, right after I change the oil, the knock on accleration is all but gone for a few hundred miles but then grow louder as the miles are put on.
The vehicle now has 60k + miles, since we've taken many long road trips, but has had regular oil changes and maintenance.
Any thoughts or suggestions?