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Forum nameTurbo/Nitrous Tech
Topic subjectTesting Vortec FMU
Topic URLhttps://forums.2gnt.com/dcboard.php?az=show_topic&forum=i8&topic_id=45126
45126, Testing Vortec FMU
Posted by extreme97nt, Mar-20-03 02:00 PM
How do I test the Vortec FMU. Im not getting enough fuel PSI anymore. I checked the vaccume line going to it and it is fine. Help! I dont want to blow her up.:nono
45127, RE: Testing Vortec FMU
Posted by Stan2gnt, Mar-20-03 02:25 PM
dont think you can in real time any more than the fuel pressure gauge. You can take it apart and check the diaphram. Replacement diaphrams are pretty cheap from Vortec direct. Could be your fuel pump or fuel pump wiring/voltage as well.
45130, RE: Testing Vortec FMU
Posted by extreme97nt, Mar-20-03 02:56 PM
I have the fuel pump re-wired and I made sure it was all ok. I guess it could be the fuel pump, Do they go bad often? it will only raise from 50 to 70 psi aw where it used to go over 100.
45256, RE: Testing Vortec FMU
Posted by Stan2gnt, Mar-23-03 02:16 AM
I dont think fuel pumps go bad often but I've just never heard of a non adjustable Vortec FMU failing in such a way. Could you have a clogged fuel filter?
45263, RE: Testing Vortec FMU
Posted by extreme97nt, Mar-23-03 05:28 AM
Well it turns out it was the fuel pump. I plugged off the return line going to the takn and my car would only make 70-75 psi. It turns out that the pressure relief spring on the walbro broke into 3 pieces. I took an allen screw and plugged off the hole for now until the new pump comes. Plenty of pressure now!