Hello to all. I am new to this site but not to diesel Benz's I have had a lot of them. But never ran into this prob. She is a 81 300SD with 300K Miles. When I start her up and she's cold, the motor misses and runs like a bag of #%&@. Have to keep the peddel down a fear bit to keep her going. Slowly she will start to smooth out a little. Then after a few seconds of driving its gone. And it does NOT loop or ldel bad when she is hot. After shes warm it runs like a dream. Now I know that a diesel with 300+ on her is not going to run smooth as glass when cold... " or ever LOL " but its the feeling that the engine is missing firing or not firing that got me. I did a valve tune-up and flushed out the fuel system. All the lines look good and checked glow plugs. I would not really care about it running this way. But its the wifes winter car and she hates that it runs like that. Also winter is comming and will get worse I am sure. Any help would be great. Thanks. I look foward to hearing and telling storys about our love for Diesel Benz's
Jay

 

I would go to this site where he has a pictorial on how to check your Glow Plugs (you will need a Volt/Ohm Meter; Harbor Freight sells them for $3).
When the site opens up you will have to scroll down the page as at first it looks like there is nothing there.
In the 2nd picture of the Glow Plug Relay; on the left you will see a metal strip. That metal strip is the Glow Plug Relay Fuse. If it is not burned take a really close look to see if it is cracked as that can be hard to see.

http://www.dieselgiant.com/glowplugrepair.htm

After doing the above let know what you found.