C_B_B

I've been noticing a tapping sound on my car. I'm sure it was only doing it when cold and when on throttle. To start with i put it down to a stone in the tyre. This morning it seems to be doing it whilst parked with the engine running.

The oil level is fine and the car has always been driven carefully for 20 minutes before using the revs as well as having been run in correctly.

It's a Forester 2.5 XT.

Any ideas as to what it could be?

I do have a warranty but i would like to know what to tell the dealer in case they try to fob me off.

chris_c201

Alright Mate,

There can be various reasons...

Cambelt Tensioner, noisy tappets, poor quality / low oil,

Mine does it mildly sometimes when cold then passes when its heated up, i've not thought about it much as so many people seem to have the same symptoms.

If you have warranty may be worth getting them to check your tensioners etc just in case, i'm sure someone will give a better, more technical answer shortly though!

lightwave693

could be piston slap, mine does it when cold but goes after about 5 - 10 mins.

justanotherperson

if this was piston slap, does that mean the rings are not expanding and,say gummed up ?
I have simular and have wondered about piston slap, although it does go after about 20mins but you can only hear it at say 800rpm but then at 900-1000rpm or above you cant hear it.My car has only 22,000 mls on the clock aswell.

maybe a few more oil changes would cure it ?????

justanotherperson

bttt for me

C_B_B

Thank you for the replies.

I'll contact the dealer about it.

lightwave693

piston slap is common with these engines, it caused by the piston being slightly to small so the skirt bangs against the side wall, but when warm the piston expands to the correctsize and all is well. its nothing to worry about unless it doesnt go when thew engine is full up to temp. do a search for piston slap. usuallly is piston 4 for some reason, other know a lot more than me on this subject.

easy diagnosis, start cold, little bit of tappy, rev gently tapping gets louder and increases with engine speed. let revs settle it goes. thats usually piston slap.

HTH
Rich

C_B_B

Thanks Rich, i think you've hit the nail on the head.