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420 SEL no power to fuel system

1K views 1 reply 2 participants last post by  MBL87560SEC 
#1 ·
I have a 1989 420 sel and have no power to my fuel pump. I have power at the input for my relay, crossing the terminals I can engage the pump and get the car to fire. It fires for only a moment and then fails as if it is running too rich. I have tested the fuel pump relay and the OVP, both are good. My pumps are also good. I got the wiring schematic from the library today and will start tracking down the problem tomorrow. I was just wondering if there is a common issue for this electrical failure, or a good place to start. Or if any one else has experience with this issue I would be grateful for any advice, or anything I should be careful for when poking around down there. Thanks
 
#2 ·
From what you say about jumping the terminals it sounds as if the fuel pump relay has failed..

That of course will not make it run poorly, but repeated starting attempts to start CAN flood the intake with extra fuel from the cold start valve .. especially when its chilly out as it is here up in New England.. You may be able to clear it by opening the throttle as it starts too.. IF you can.. keep it running 'til the coolant temp rises appreciably..

When you take a few moments to fill out your profile details that will help other members assist…..

Good Luck

MBL
 
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