1986 iroc died. Fuel pump not working.

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Jul 28, 2014 | 05:18 PM
  #1  
I put power to the connector under the dash into the g port and i can hear the fuel pump go on. I try to do the paper clip method to pull a code and the service eng light wont come on. I pulled the fuel pump relay off and I have no power going to any of the terminals. I have checked every fuse in the block and the one by the battery and they r fine. I cant find the gray wire that is suppose to power up for 2 seconds by the relay. The car is bone stock. Any suggestions??
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Jul 28, 2014 | 09:55 PM
  #2  
Re: 1986 iroc died. Fuel pump not working.
To be sure I'm looking at the right diagram, how many wires and what colors go into your fuel pump relay? You didn't say what engine so I assumed 305 TPI. You should have system voltage at all times on the orange wire at the relay. If not, inline fuse number 8, 20 amps should be checked.
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Jul 29, 2014 | 04:58 AM
  #3  
Re: 1986 iroc died. Fuel pump not working.
There is 2 orange wires and 3 other going to the fuel pump relay. Neither of the 2 orange have power. Where is in line fuse #8?? The car is a 305 tpi.
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Jul 29, 2014 | 10:13 AM
  #4  
Re: 1986 iroc died. Fuel pump not working.
Sorry, that was supposed to be fuse number 2 not 8. According to my info, it's at the battery. Check any 20 amp fuses you find by the battery. Look around real good. One Orange wire goes to the Diagnostic connector. The other gets it's power from that inline fuse. Now that I know we have the right diagram, I'll include it so you can see what you have. One word of caution, be absolutely certain your multimeter has a good ground while you are checking things. You don't need that to throw you off.

1986 iroc died.  Fuel pump not working.-86-iroc-fuel-schematic.jpg  

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Jul 29, 2014 | 03:48 PM
  #5  
Re: 1986 iroc died. Fuel pump not working.
Thanks man. That was the 1st one i checked, its fine. i even checked it with a test light. When I do the paper clip test on the computer port under the dash, the service engine light doesn't come on. do u think the ecm is not getting power also?
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Jul 29, 2014 | 11:24 PM
  #6  
Re: 1986 iroc died. Fuel pump not working.
Does the SES light come on normally when you turn the key forward? You know, the bulb check test. First thing would be to make sure the bulb is working. I'll get the wiring for the ECM so you can test it.

You checked fuse 2 and you say it's good. Does it come out of that fuse on an Org/Blk wire like the diagram shows? I'd use a meter so you know the exact voltage. Following the diagram, if the voltage is there it goes through a connector. Can you see that connector? If so, I'd check after the connector to make sure power is still there. Diagram shows it leaves there on an orange wire and goes through splice 163. My info says splice 163 is at the top rear of the engine. If you find where that voltage stops, then you isolate where the problem is.

1986 iroc died.  Fuel pump not working.-86-iroc-ecm-wiring.jpg  

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Jul 30, 2014 | 10:33 AM
  #7  
Re: 1986 iroc died. Fuel pump not working.
When the car was running good. The ses light would com on during start up and then go out. When i would do the paper clip test to pull the codes, it sounded like the fan would come on and the ses light would flash the code that whatwas wrong for it for the day. When i put the paper clip in it now nothing happens, no fan, no codes. Do u think my ecm is dead?? I have no power at the fuel pump relay with the ignition off or on. I have the ecm pulled down. I Will see If I have power going to it.
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Jul 30, 2014 | 09:08 PM
  #8  
Re: 1986 iroc died. Fuel pump not working.
It's possible. It will be interesting to see your test results.

Here is a really good video. It's long but very informative.

http://video.search.yahoo.com/video/...8c&age=0&&tt=b
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Aug 2, 2014 | 07:46 AM
  #9  
Re: 1986 iroc died. Fuel pump not working.
Found the problem. The wires in the loom in the back of the engine came apart.

Thanks for your help.
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Aug 2, 2014 | 11:11 AM
  #10  
Re: 1986 iroc died. Fuel pump not working.
Quote: Found the problem. The wires in the loom in the back of the engine came apart.

Thanks for your help.
Great job. The electrical diagram led us to splice 163 and it appears that is where your issue was. How's it running now?
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