m30 timing chain tensioner/guide rails

[eugeman]

I am getting a slight chattering/hissing sound for the first 30-45secs when the engine is cold - normal driving & when the engine is warm @3500< rpms. Valves were adjusted approx 5,000km's ago.

Does my timing chain tensioner needs to be replaced? If this is the case, would it be safe to assume (without opening up the engine) that the guides would be in reuseable shape?

TIA.

[yert315]

could be. If you are replacing the tensioner you might as well replace the guides. If they are original they could have serious grooves which can loosen up the chain. Also think about getting a new chain while you're at it. They don't stretch like a belt, but you'll need to remove it anyway.