Crank no start fuel pump not priming?

2003 JEEP LIBERTY
150,000 MILES • 3.7L • 6 CYL • 2WD • AUTOMATIC
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JSNYDE
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  • 2 POSTS
No engine light upon first crank fuel pump not priming or getting power replaced fuse relay and fuel pump still no power to pump charged battery cleaned ground
Feb 10, 2026 at 11:18 PM
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STRAILER
  • ✓Experienced Mechanic
  • 55,065 POSTS
So if the MAP sensor does not give a signal the engine is cranking over by not showing a reading the engine will not start, I would unplug the sensor and the PCM will substitute a default value to help the engine start, here is the location of the sensor. Check out the images (below). Please let us know what happens. Ken
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Feb 11, 2026 at 1:53 AM
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JSNYDE
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Crankshaft positioning sensor ? Also when I crank over my tach doesn’t jump anymore
Feb 13, 2026 at 4:50 AM
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STRAILER
  • ✓Experienced Mechanic
  • 55,065 POSTS
O ya, if the tach is not working when cranking the I would replace the crankshaft angle sensor. Please go over this video as well

https://www.youtube.com/watch?v=lXLJbuAZ4CE

Check out the images (below). Please let us know what happens.
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Feb 14, 2026 at 12:33 AM
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