News:

Reminder to CLC members, please make sure that your CLC number is stored in the relevant field in your forum profile. This is important for the upcoming change to the Forums access, More information can be found at the top of the General Discussion forum. To view or edit your profile details, click on your username, at the top of any forum page. Your username only appears when you are signed in.

Main Menu

1976 eldorado fuel pump

Started by Harley e, February 26, 2023, 04:29:36 PM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

Print
Go Down Pages1
User actions

Harley e

February 26, 2023, 04:29:36 PM
Good afternoon all. Update and question on my 76 Eldorado convertible with fuel injection. Got the car not running with no keys. Cleaned it up and got it ready to run got clean gas, new injector seals, filter and oil. I am not getting power to the fuel pumps. I ran a hot wire from the battery cut the power wire and hooked the hot wire to the pump. The car runs like it is brand new. So my question is can I run power to the pumps off a key on source with a fuse or relay? Or does the power need to come from the ECM? Thanks. I am super excited to have a running car now.

bcroe

#1
February 26, 2023, 08:42:45 PM
Quote from: Harley eGood afternoon all. Update and question on my 76 Eldorado convertible with fuel injection. Got the car not running with no keys. Cleaned it up and got it ready to run got clean gas, new injector seals, filter and oil. I am not getting power to the fuel pumps. I ran a hot wire from the battery cut the power wire and hooked the hot wire to the pump. The car runs like it is brand new. So my question is can I run power to the pumps off a key on source with a fuse or relay? Or does the power need to come from the ECM? Thanks.
.

Glad the car runs well, the 76 EFI fuel pump problem
is common and permanent fixes have been worked out.
For safety the ECU only runs the fuel pumps when the
engine is turning, otherwise an accident damaging the
fuel system might pump out the entire tank of gas on
the scene.  Your ECU needs some work, not very costly,
and a retrofit relay will avoid the issue in the future. 

For openers, I recommend examining the ECU connector,
you may see the in the very center, pin C is burned
out and not supplying pump power.  If the pin is OK,
the problem is likely inside the ECU, but repairable. 

I have fixed a hundred of these, contact me at
bcroe@juno.com
Bruce Roe with 79 EFI Eldo, CLC # 14630

Chopper1942

#2
March 01, 2023, 08:14:31 AM
If the pin looks OK, back probe the terminal with a T pin.  Get a headlight (2 terminal is easiest) and, with a jumper wire, connect 1 terminal of the headlight to the T pin at the ECM and, with another jumper wire, to the other headlight terminal to a good ground.  Turn on the ign.  If the headlight comes on bright for 1-2 seconds, the ECM is probably OK.  Now crank the engine.  The headlight should stay on while you are cranking the engine. If it does, your problem is high resistance or an open between the ECM connector and the fuel pump. Use a DMM in the ohms position, with the ECM connector and the fuel pump leads unplugged, connect the meter leads to the ECM's fuel pump wire (the T pin you installed) and the fuel pump connector. Check the resistance.  It should be less than 2 ohms.  If the reading is greater than 2 ohms or is OL, you have a wiring issue. Hope this helps.   Good luck!
Print
Go Up Pages1
User actions