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1997 B1500: New fuel Pump but no fuel pressure

6K views 9 replies 3 participants last post by  BubblesPT  
The fuel pump will come on briefly at 'key-on' to prime the lines/rails. If the PCM does not sense engine rotation through the crankshaft position sensor, it will shut off the ASD/fuel pump relay by lifting the relay coil ground.

Was there debris at the bottom the tank that might have been ingested into the new pump? You can determine a plugged filter sock with a visual inspection.

When you blew out the fuel line with compressed air, were you able to get a good flow of air out the other end? I've had fuel lines rust themselves shut on the inside while looking OK on the outside.

Do you hear the pump 'hum' briefly at key-on? Can you discretely power the pump with a 12 volt source and capture the fuel flow into a clear soda bottle?
Use fire precautions around raw fuel or fumes. Keep sparks away. Don't allow the pump to run dry.

If it sat for 2 years, I suspect that the fuel rail & lines dried out. The inside of the rail may be rusted or gummed up from dried fuel?

Is it low fuel pressure or low fuel volume? Are there bubbles or foam along with the liquid fuel? You want about 50 psi (345 kPa).
 
There may be some wire color differences between the pickup & the van.
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Intermediate connectors, grounds & sometimes splices are common weak spots.
See if you can find the 8W chapter that shows their locations. Inspect for corrosion or damage.
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