Arghhh

My '01 Civic has recently started sounding like a diesel truck with a loud, continuous rattling noise coming from the belt side/area of the engine.
- I hear it most when idling
- it doesn't change when revving up the engine in neutral, or shifting into reverse or drive
- I don't hear it when driving on the freeway, but maybe the sound is just masked by road and normal engine noise at that point
- no problems with the car stalling in idle or losing power or shifting

Last week I had a different lighter rattling noise that I noticed only when in in lower rpms in first gear and didn't step on the gas too much - once I stepped on the gas pedal a bit more I could get the sound to stop. I think the other noise described above has replaced this one...

A couple other points:
- replaced timing belt 20,000 miles ago, so kind of doubt that's it, but the sound is coming from that area
- exhaust manifold is cracked (and has been for 5 years), but wouldn't noises originating from there be variable based on engine speed?


Any ideas?

lazlong

Was the tensioner replaced when timing belt was done? Could be one of the pulleys is going bad.

An exhaust leak would sound kinda like a diesel but, would get louder the higher the rpm. Could be the exhaust manifold heat shield is rotted out.

To help pinpoint: You can CAREFULLY take a long screwdriver, touch the working end to different parts and your ear to the handle.

prodjay10

I had a cracked manifold that sounded like what you are describing however it would get louder when first accelerating but then the engine or road noise would drown out the sound. Replaced them and the sound went away.

Arghhh

Took it into the shop today, they took the cover off and found that the timing belt tensioner spring had broken off and got caught in the timing belt. Luckily it hadn't caused the belt to jump yet. Yay for a $450 repair...

prodjay10

No warranty on the timing belt?

Arghhh

Make that $650 now because they found the tensioner was worn at the spring attachment point and are replacing that too. Arghhh!

Probably no warranty on the belt either as I had it replaced five years ago at a shop 2000 miles from where I currently live. They said they only give one year warranty on most parts and labor and the warranty work must be done in their shop.

lazlong

Expensive but, you could be replacing the engine for way more money. ALWAYS ALWAYS ALWAYS replace the tensioner too.