I have a 2007 caliber SXT 2.0. I recently replaced my alternator and battery and serp belt. Along with many other parts. The alternator and battery were replaced Oct 1. Everything was running smoothly until yesterday. While accelerating I noticed a really loud noise, similar to a diesel truck or a a fake Honda race car with a really bad muffler/exhaust!! I opened the hood and put my ear to different parts and it's coming from the engine. My ex-boyfriend said I need to replace the timing chain at some point. Could this be what is making the loud noise? It makes the noise the second I start the car up and as I accelerate, it gets increasingly louder. Almost like I'm about to take off. When I'm idling, it's a little softer of a noise but still noticeable. What the heck could it be?! Thanks in advanced.