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DISCUSSION => Electrical => Topic started by: txleadfoot on April 18, 2008, 12:09:50 PM

Title: Test Fuel Pump Connection
Post by: txleadfoot on April 18, 2008, 12:09:50 PM

How do I test the electrical connector at the fuel pump with a multimeter?  I can't get a reading on any of my running 318s with the ignition on.

Title: Test Fuel Pump Connection
Post by: Cobra Jet on April 18, 2008, 01:13:26 PM

I'm gonna say do a KOEO test (key on engine off) - once you have the car on and there is power, you should be able to get a 12 volt reading at the connector IF power is going to it.  Set your mult-meter to "DC", then take the multi-meter leads and touch the fuel harness metal prongs within the connector...  if everything is fine, you should see some sort of read out on the multi-meter.

Title: Test Fuel Pump Connection
Post by: RED IS 91 on April 18, 2008, 03:43:23 PM

Make sure your testing the pump leads and not the fuel guage leads.The two in the photo are the pump leads.
(http://i141.photobucket.com/albums/r73/bogeyman700/fuelpump2.jpg)
good luck

Title: Test Fuel Pump Connection
Post by: txleadfoot on April 18, 2008, 05:57:04 PM

I get nada.  Even tried using the chassis as a ground.  Also tried another working multimeter.  This is on 3 cars, two of which are running.  I'm stumped.  Yes, it's the wiring at the pump, not the fuel level sender.

Thanks for your help,
Shaun

Title: Test Fuel Pump Connection
Post by: RED IS 91 on April 18, 2008, 06:37:41 PM

Check your relay?

Title: Test Fuel Pump Connection
Post by: txleadfoot on April 21, 2008, 09:49:10 AM

Thanks for the help guys.  I discovered over the w/e that there is no juice to the fuel pump.  It appears to have been cut previously at the connector end, so I will start there.  Is that wire set part of a larger harness, or can it be replaced with a factory section?

Title: Test Fuel Pump Connection
Post by: ak96ss on April 21, 2008, 06:30:07 PM

IIRC, it is part of the whole harness coming from the front.