Sometimes on starting engine I get a small cloud of grey smoke and sometimes not. Setting in park idling and racing engine it will not smoke. Put in drive while idling it will not smoke, foot off brake and drive off and sometimes there is smoke and sometimes not. Timing is set at 12 degrees like manual calls for. Any ideas?

Thanks in advance

Sounds typical of worn intake valve seals....shows up as a puff of smoke after idling for a bit. Idling is a high vacuum condition that draws oil past the leaky valve seals, then gets burned as you step on the throttle.

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95 E320 Cabriolet, 159K

Thanks for quick reply. I was afraid that was what someone would say. Any idea as to what has to be done? Complete valve job or what? Any range on the cost?

I'm not familiar with your engine. Sometimes they can be replaced without removing the heads. The tricky part is to keep the valves from dropping down into the cylinder. If the valve guides themselves are sloppy, new seals won't last long from all the wobble and enlarged leak path and the head should be reconditioned.

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95 E320 Cabriolet, 159K