I recently noticed concerning sound coming from the engine bay of my 1.6 2002 Civic. I tried to record it but for some reason it seems to be difficult to catch as engine noise covers most of it:

Vocaroo | Voice message

Maybe you can hear that pulsating "rumbling" sound especially in the end? It appears to come from timing belt side of the engine and can only be heard when engine is idling. Timing belt and water pump were replaced couple of months ago, and I already tried to run the engine without aux belt to rule out bad AC pulley bearing but noise was still there. It can't be gearbox/clutch either as they are on the other side and depressing clutch pedal doesn't affect this sound. Could it be my luck and new water pump is going bad? It's not leaking coolant, yet anyway but shouldn't bad water pumps usually leak?

 

Wecome to the forum. No water pumps don't have to leak to be bad. The bearing inside can go bad n make noise but no leak. Or no rumble n leak water. Take it back to the place that changed it and tell them to fix it. I have mine done by a good mech who purchase all ho ha parts I don't worry until next change. Timing belt change is with cam seal crank seal water pump n gasket tensioner.

 

I'll bet it was a reman water pump,it happened to me once ,I put a pump on and a week later it went bad.

 

i personally only use NAPA water pumps which i believe are made by BOSCH.

 

I took the car back before christmas for checkup and they thought that tensioner that came with Contitech timing belt kit didn't keep the belt thight enough so they replaced it with original Honda timing belt kit and after that no more noises. Except leaking exhaust manifold that makes loud tapping noise when it's freezing cold, whining gearbox and screetching clutch pedal