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4.0 HO swap fuel presure problems..... HELPPPPPPPP

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So I have been bulding a MJ and i have a 4.7 stroker that was bult out of a 99 block 93 head and 99 intake/w a hiseco tb adapter and a 95 fuel rail every all of the sensors are from the renix motor. My question is what is the fuel presure supose to be at the fuel rail? I just replaced the pump in the tank and I have good presure before the fuel regulator but after i prime the pump i don't seem to have any presure after the regulator. If i press on that relife valve on the rail barly any gas comes out i replaced the fuel regulator and with both of the o-rings i diden notice any presure at the rail but if i took of the first smaller o ring off i got a little more presure at the rail but no spraing just a slight (very slight) dribble... I don't want to skrew up the new motor bu cranking it to much with out breaking it in so what do you think?.... :huh???:

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Fuel pressure should be 39psi and have you checked to see if you have the lines crossed? meaning presure to return and return to pressure as that would make the rail have NO pressure....


Remove the two lines and have a bucket ready to put them into then have some one jump the Fuel pump Relay and see which one has fuel comming out if none then you have a pump problem...

The fuel inlet should be the one without the regulator and the larger of the two lines for the 95 Fuel rail...


Good luck

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