Just bought a 1993 300D from down south. Here in Colorado, when cold (30 degrees F) it starts, runs fine for 20 seconds, then begins the clunking nailing sound and has heavy smoking at idle.

Once the car warms up, it's just fine, and the car runs and idles very well.

I did notice a tiny fuel leak at two of the injectors as well as some air bubles at the base of one of the injectors.

My theory so far is that the injector seals at least need replacement. Any help or advice would be appreciated.

Also, where is a good place for seals or injectors and does anyone have a link for injector removal/replace procedures?

Thanks
Bob