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Mike, Mechanic
Category: GMC
Satisfied Customers: 39198
Experience:  Hi, I have been a Car/vehicle mechanic 34 years. 29of -running my own repair/diagnostic business.
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Ihav a 2000 Chevy Astro Van had bad motor 210,000 miles I

Customer Question

ihav a 2000 Chevy Astro Van had bad motor 210,000 miles I purchase a 2003 GMC Safari van with 19,000 miles I swapped motors with transmissions. I chose to swap engine compartment wiring harness and ECM the harnees apprears the same and plugs right into the fire wall in the engine compartment but there was one extra termainl on the old harness that the new harness did not have van turns over but no start arrears that the fuel pump is not powering up??
Submitted: 1 year ago.
Category: GMC
Expert:  Mike replied 1 year ago.
Hello and Welcome -
My name is ***** *****
Its difficult from here to say exactly what that wire would be - but, as you have no power to the fuel pump, it could well be that circuit.
The Ecu / computer powers the fuel pump relay - and then that powers the pump - ( some go through then a fuel cut off switch - check of you have that first ! )... if thats all it is, thats that done.. If not - then check the power feed to the relay. If its not there - you then need to check the feed from the ecu to the relay... If it is there- check then the circuit to the pump.
You can if its there, by pass the relay pins to see if the pump will feed - it should.
One way or the other as above you should get this sorted .
Let me know how you go or if you need anything else / more -
~~~~ Meantime - Please do click on the "Exc / Ok rating" for me at this time.. "Thank you" in advance for that .
.. Note that you can get back to me anytime at all after doing the rating - it doesn't close you out.
-- Best Rgds, MIKE.