Grinding when accelerating 2003

Hey there,

Have a question. I have a 2003 Mustang and just recently when I step on the accelerator there is a grinding feeling going on. also when I put the car in park the engine will rev up. Could this be my fuel filter? I am not a smart person when it comes to cars. My Mustang has about 120,000 miles on it and I keep it in good shape. I get my oil changed when I'm suppose to and I don't drive it like a maniac. I just want to make sure I know what I'm talking about when I take it in.

thank you to whoever can help me with this question.

Hey,

it's feels like the grinding is coming from just behind the engine and when I went to work as I stepped on the gas it kinda felt like it was going to sputter a little bit. Man I hope that makes sense.

I filled up all the way with gas and I let the car run before leaving for about 15 minutes and it the engine didn't rev like it did before.