Mercedes Benz repair: starting problems, backyard mechanic, fuel pump relay

Question
Hi whunter,
   I own a 89 mercedes 300e with 140,000 miles.  I was driving on the freeeway and suddenly my car lost power and "died".  I had it towed home. My car cranks but will not start.  I'm a do it yourself backyard "mechanic"-own oil changes, and tuneups.  Can you help me with a step by step approach how I can fix diagnose the problem (diagnosis)? Your help is greatly appreciated.  Thanks in advance.

Sincerely,
Stan

Answer
Read these threads.

Car no-start troubleshooting
http://www.samarins.com/diagnose/

Rapid no-start diagnosis
http://www.findarticles.com/p/articles/mi_qa3828/is_200305/ai_n9271467

300 E Died on Highway
http://www.mercedesshop.com/shopforum/showthread.php?p=282561#post282561

alternator, battery relationship
http://www.mercedesshop.com/shopforum/showthread.php?p=376463#post376463

misfiring, rough idle, poor mpg, undriveable!
http://www.mercedesshop.com/shopforum/showthread.php?p=686293#post686293

For heavy continuing technical support, I suggest you join:  http://www.mercedesshop.com/shopforum
As a member, you can "Advanced Search" this:

300E fuel pump relay

http://www.mercedesshop.com/shopforum/search.php