Engine - Noise When Cold
SOURCE: Subaru Tech Tips
TITLE: Engine Noise When Cold
APPLIES TO: 99-00 Impreza/Legacy/Forester 2.2/2.5
SERVICE TIP:
Subaru has received several reports from the field of an engine noise that could be mistaken for an internal engine noise.
This noise is heard after a cold start and will gradually go away as the engine warms up. It may therefore be difficult to reproduce unless the vehicle is left overnight. The noise sounds like it comes from the front of the engine and could be mistaken for failed bearings.
It has been found that the timing belt tensioner on these vehicles may be weak allowing the timing belt to move and hit the inside of the timing belt cover. The bearing itself could also be at fault.
Please make sure you listen to the actual noise before reaching a diagnosis.
If you suspect the belt tensioner, remove the front cover and look for evidence of rubbing or chafing.
Note that once removed, the timing belt tensioner feels fine.