Tapping sound from engine

[bondale]

Hello Everybody,
I have a 1996 E320 sedan with 164K miles on it. The problem is when I start it in the morning,it cranks so highas if the throttle is pressed Vroooooom, then runs at 1000rpm before it gradually comes down to normal a little above 500. While doing this I hear a tapping ( ?valve) sound coming from the engine. This sound gradually reduces as the engine warms up and disappear when fully warm. What could this be. Please help. This is my daily driver. Thanks.

 

[television]

As the weather gets colder, your car will behave differently than in warm conditions and will stay on higher idle for longer periods. The head and block also take longer to reach normal operating temperture. It will be valve gear that you can hear, but that's OK for 160k miles.

Malcolm

 

[C220GJS]

Check your throttle linkages are well lubricated ,operating smoothly and there are no broken or missing return springs.

 

[Stevie A]

As Malcolm says the engine revs itself up when starting. The taps are the "valve lifters" or tappets I think. Don't worry about it if it is not tapping when the engine is warm. Someone posted last week saying thay'd had noisey tappets on their car on warm up since 1987.

 

[bondale]

Re:Tapping noise in engine.

Thanks for all your responses. I appreciate them and will let you know what becomes of the noise as time goes on.

 

[GEORGEROV]

I use a 15w/50 oil in my 500se and this keeps the hydraulic lifters quiet on start up.

 

[television]

I use a 15w/50 oil in my 500se and this keeps the hydraulic lifters quiet on start up.

This is a good point, one that I had forgot, when synthetic oil first came out, it was not for use in worn engines, at what point do you change to a 15/50w oil,150k. the whole point here is that if you can hear the valve gear,more wear is taking place than if you cant hear it.

Malcolm