View Single Post
Old 09-02-2003, 08:52 PM
telefunkin telefunkin is offline
Registered User
Join Date: Jan 2002
Location: Coeurd'Alene Idaho
Posts: 48
fuel pump relay mystery

Howdy all,
1989 300E 180K.
Car died comming to a stop light. Pushed her off the road and found that it was not getting fuel, allthough I could here the pumps working......Infamous pump relay!
Replaced the relay with new and everything was fine...for about 30 days then she died again. Again no fuel. Refering to this handy dandy site I learned how to jump the relay....connecting pins # 30 to 87 on the new relay. (saved on towing. Thanks mercedes shop).
Today the car saw my tech, he pulled the pump cover and both pumps seem to be operating fine. When we pulled the relay apart the new one had a burn spot in the exact same place as the old one. He re-soldered the break and now of course she starts right up without my jumper cable. My Question is what could be burning out my relay?
Could there be a poor or no connection on one of the pins (fe-male end)?
With #30 and #87 jumped my pumps run without a key in the ignition. Is this normal?
By the way the ovp is new and the fuse is good.

Any help will be greatly appreciated.

Thanks, Brian
Reply With Quote