Ok I replaced all five glow plugs to defeat my starting problem. This was a success.

I back the car out and after about 700 ft a tap tap tap sound is coming from either the engine bay or under the car. It coinsides with the speed of the engine.

However, when I manually rev the engine while it is in park from under the hood, the sound is not really pronounced, I cant even tell if it is there. I am going to pick my indy's brain tommorow, but I hope its not engine trouble. The car has been running perfect and I have never had any engine related issues.

Any comments?

__________________
http://www.betten.mercedescenter.com...n_banner_1.jpg
1976 300D
190,000 Miles
Colorado Beige

1975 300D
Parts Car
78,000 Miles
Rustbucket
Also Colorado Beige

1984 190D 2.2 (Dad's)
156,000 miles
Champagne Metallic Clearcoat