Here's the scenario. On Sunday I noticed my engine was making a knocking sound (while it was parked - I started it with my remote starter). After driving home I couldn't hear it anymore. Thought it might be due to the temperature. 2 days later I drove to work and after parking and opening the door, I heard it again. But after driving home that day it wasn't doing it anymore. Finally yesterday it did it when I got to work and when I got home (as well as when I was stopped on the highway). It seemed to get faster then go away as i accelerate (or maybe i just can't hear it anymore).

Any ideas?

It's a 2005 sedan 2.4L with 87k miles.

 

After dropping it off at the shop for a few days they narrowed it down to a cracked flexwheel I believe they called it. All in all it cost me about $975 to get it fixed. It took care of the knocking noise after it was replaced.