As suggested, it does sound somewhat like engine ping. Does it go away when the engine is warm? Engine ping will be there all the time cold or warm. Quick test for ping is to buy a tankful of 93 octane fuel to see if it goes a away with the addition of more octane. Optionally, you can toss in a bottle of some good quality fuel injection cleaner when filling up with the 93 octane (such as Techron Concentrated Fuel System cleaner). That combination should help clean your fuel system and might help eliminate the problem. This has worked for me in the past.

Could also be a little valvetrain noise. That should go away or at least quiet down once the engine is warmed up. My engine (289k) also seems to make a clicking type sound when cold that goes away after warming up. Considering the mileage a little valvetrain noise isn't surprising. My 850 (108k) also makes some valve related noise when cold that always goes away once warm.

Do you live in a cold climate? The clicking/valve train type noise is worse in cold weather.


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93 850GLT 108k, 90 244DL 289k and running well again :)