Friend of mine has a 2.0l 2001 Forrester Auto.

30k, full SH, one elderly previous owner.

The other week he started it up, and there was a knocking from the engine. Only from one side.

It's not getting worse just more regular. Now it is every cold start. Goes away when warm or sometimes if you turn off and restart.

I know there are common issues with the big ends and piston failure with this engine, but has anyone else had any similiar experiences?

Heard the cam belt tensioner can also go awol, causing the belt to come into contact with the cover.

Any help would be appreciated, as at the moment it's laid up.

Cheers

J

 

i'm not sure, but if it was a bearings, wouldn't it knock all the time (regardless of hot / cold)?

Some impreza's suffer from piston slap, so maybe the forrester does as well?

Edit: piston slap is apparently mostly audible when the engine is cold.

I believe piston slap is when the cylinder isn't 100% round when cold (or is it the piston). This causes the piston to knock into the cylinder wall, which causes a knocking sound. It usually disappears as the engine bits get hot and expand and allegedly it's not fatal.


Health warning: I've only read about the above, I've never heard a slapping piston, nor do I know for sure if the above is the cause for piston slap.