I'm hoping something in the engine bay is just loose, but is it possible to check minor rod knock with the engine still in tact? Could a misaligned timing belt cause internal noise(possibly piston slap?). I believe I have a HG leak and might be mixing with the oil and damaging the crank?? The engine(internals) only has 140 miles on it.

 

Piston slap is very common on the neon.

What does the problem sound like? Does it get louder with RPMs? Does it go away when the engine warms up?

 

piston slap has nothing to do with the alingment of the timing belt.

Its hard to know exaclty since so many things make noise, could be rod knock, lose wrist pin, valve chatter, piton slap, or failty lash adjusters. Best way to know is buy pulling the pan.

 

My neon engine sounds horrible...I'm glad I've got a spare motor which sounds dec.

 

Um just sounds like metal lol. I guess its easier to hear by the exhaust manifold. do need to get the head resurfaced so perhaps its slapping it? I'll go pull the pan in a bit, I know how to check the knock but what other things should I check for, just check torque on all the bolts and wiggle stuff lol?

 

http://www.allpar.com/fix/chatter.html