1991 Dodge Shadow Fuel pump power but not working

Tiny
JUSTDON
  • MEMBER
  • 1991 DODGE SHADOW
Engine Performance problem
1991 Dodge Shadow 4 cyl Front Wheel Drive Automatic

Replaced fuel pump and filter. Pump still did not operate with the key on. Car ran with starting fluid.

Checked battery voltage and found 12V. Checked voltage at the fuel pump electrical connector and found 10V. Placed direct battery voltage to fuel pump and the pump operated until direct voltage was removed.

Fuses checked okay. I'm not sure of any relay locations or diag procedures for them.

Please Help!
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Wednesday, June 11th, 2008 AT 6:35 AM

17 Replies

Tiny
BMRFIXIT
  • EXPERT
Check fuse # 2 20amp its fuel pump fuses
you have a shorted wire
i would check the fuse and its connections 1st
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Wednesday, June 11th, 2008 AT 6:53 AM
Tiny
JUSTDON
  • MEMBER
Thank you for such a fast response.

I actually switched the fuse with another 20 amp. And still nothing. I assume this shorted wire can be anywhere from the fuse box to the pump?

I guess I'm going wire fishing. Lol

Thanks again
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Wednesday, June 11th, 2008 AT 6:59 AM
Tiny
BMRFIXIT
  • EXPERT
Sorry I tried to load up the wiring diagram for you. I noticed that I sent you something else in error. I will correct it when I get access to my data later tonight.

Mean-while check the wiring harness
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Wednesday, June 11th, 2008 AT 12:32 PM
Tiny
JUSTDON
  • MEMBER
No problem. I'm just glad for the assistance.

I did find one odd thing so far. There isn't any power to the fuel pump fuse with the key on or off. But I have a steady 12 volts to the pump connector as long as the key is on ( 12 volts since I charged the bat.) But the pump will not run without direct battery voltage. Can you explain how this could be?

I don't have much more hair to pull out.
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Wednesday, June 11th, 2008 AT 12:47 PM
Tiny
BMRFIXIT
  • EXPERT
It can be very frustrating looking for a short
u noticed very important issue that fuse # 2 has no power
that fuse is supplied power by the ASD relay
I would like you to check the relay and its connections
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Wednesday, June 11th, 2008 AT 5:01 PM
Tiny
JUSTDON
  • MEMBER
BMRFIXIT;

Since the price was low, I just purchased the relay. After installing it, I still had no pump action. I held a test light at the fuse, turned the key to "On" and the test light lit with a relay click for 2-3 seconds. When I tried to crank, the test light lit as I cranked the engine. The car must have needed that relay also.

Still power to the pump connector with the key sitting in the "On" position. Oddly enough, if I pull the Fuel Pump fuse at that point, the voltage to the connector drops to "0". Would this mean that the problem is "before" the fuse block?

One other thing, to confirm that there was spark, we used starting fluid when I tried the cranking and the car ran until the starting fluid burned out. The person helping me said that he could hear the TBI clicking as I cranked. But of course, no fuel was being sent.

I thank you for all of your help. I will be making another donation when I get paid since you have spent so much time with this.
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Wednesday, June 11th, 2008 AT 8:21 PM
Tiny
BMRFIXIT
  • EXPERT
The concern is know for the dark green /black wire
you have power at the fuse that is a step in the write direction
check if you have any battery power at the gas tank wires
dark green/black wire should have battery power because it is supplied by that # 2 fuse
and if not you have to check the wiring harness for a short in that wire
also check the black wire it should show a good ground
if u like u can run a wire from that fuse all the way to the back

it will be a better if you can locate the short
let me know
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Wednesday, June 11th, 2008 AT 8:45 PM
Tiny
JUSTDON
  • MEMBER
One thing that I thought was a problem was that the fuel pump connector has a steady 12 volts even if the car is just sitting in the "on" position without the car running. I thought that the power was cut by the relay after a few seconds if you don't crank the engine.

Should there be current to the fuel pump connector with the car not running but just in the ON position?
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Thursday, June 12th, 2008 AT 3:50 PM
Tiny
BMRFIXIT
  • EXPERT
Can you tell what color is the wire
that have a battery power
is it the dark green/black wire
let me know
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Thursday, June 12th, 2008 AT 5:13 PM
Tiny
JUSTDON
  • MEMBER
It is the dark green/Black
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Thursday, June 12th, 2008 AT 6:02 PM
Tiny
BMRFIXIT
  • EXPERT
It should have battery power only when 1st key on and or when cranking
its activated by the ASD relay circuit
know we know that the relay is working and the fuse is OK
so the circuit is good between relay and fuse
so we have a short to power in that circuit between the fuse and the pump
just make sure no one had rigged it before
check that wire
it should be from the fuse to the pump
you may have to open the wiring harness AND trace the wire
also make sure you have a good ground at the black wire

let me know
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Thursday, June 12th, 2008 AT 6:13 PM
Tiny
JUSTDON
  • MEMBER
I'll check on that right away. You're the best

I did notice that if I pull the coil plug, the power in that wire at the pump connector drops to zero until I plug the coil back in. Is this also normal?
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Thursday, June 12th, 2008 AT 6:19 PM
Tiny
BMRFIXIT
  • EXPERT
No
Check for added wires
this is what I thing
the relay was bad
they didn't find what was going on so some rewired to the coil and know that wire is shorted some where
what I would do I will try to locate where they did the wiring
and check it
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Thursday, June 12th, 2008 AT 6:32 PM
Tiny
JUSTDON
  • MEMBER
I really appreciate all the help. Obviously, it may take me a bit to complete this task. I will get back with you with what I find.

More food for your piggy bank is coming tomorrow :)
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Thursday, June 12th, 2008 AT 6:37 PM
Tiny
BMRFIXIT
  • EXPERT
Thank you

i will be here to help
just let me know
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Thursday, June 12th, 2008 AT 6:41 PM
Tiny
JUSTDON
  • MEMBER
The problem was located and the fuel pump is working great now.

The problem was a ground wire had corroded at the bolt due to time and a leak in the windshield. It corroded to the point of no contact with the body of the car. There were three black wires that were soldiered to a small piece of metal inside the harness (I thought Ford was the only Mfgr. With crazy ideas). There was then another wire soldiered to this bare metal piece and going to a bolt on the drivers side at the bottom of the trim beside the emergency brake pedal. The harness Is supposed to be in a plastic runner going down the body from the drivers door to the firewall. This plastic had broken and (over time) allowed the harness to ride down to the floor panel where there was moisture from a leak in the windshield. And caused the harness to be stepped on for quite some time.

Well, we all know what time and moisture will do to exposed metal.

There was also a problem with the cooling fan not having power. Someone had run a jump wire to power under the hood. By fixing this ground, the cooling fan was also corrected.

Thank you so much for the help on this.
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Sunday, June 15th, 2008 AT 8:07 AM
Tiny
BMRFIXIT
  • EXPERT
Happy for you
all worked OK

and thank you

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Monday, June 16th, 2008 AT 4:52 PM

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