What is causing the injector to stay open

Tiny
PCHEFSONYA
  • MEMBER
  • 2002 DODGE CARAVAN
I have a 2002 Dodge caravan 3.3l that came in running rough. It would not communicate with the scanner. I replaced the PCM and still no communication with scanner. Compression test showed no compression on cylinder 1. Rings were washed out in that cylinder from Injector 1 dumping fuel. Installed new engine and still no communication with scanner and still dumping fuel on Injector 1. ANy ideas where to go from here?
Monday, August 13th, 2012 AT 11:36 PM

7 Replies

Tiny
ASEMASTER6371
  • MECHANIC
  • 52,796 POSTS
Remove the harness to the cylinder and see if it still dumps fuel. It may be a bad injector

Roy
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Tuesday, August 14th, 2012 AT 12:04 AM
Tiny
PCHEFSONYA
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  • 31 POSTS
I unhooked the harness at the injector and installed a NOID lite, instead of a pulse I got straight NOID light, steady light no blinking.
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Tuesday, August 14th, 2012 AT 12:11 AM
Tiny
ASEMASTER6371
  • MECHANIC
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Ok, the return wire to the pcm is grounded causing this condition. You need to trace the wire back to the pcm to find the ground.

Roy
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Tuesday, August 14th, 2012 AT 12:20 AM
Tiny
PCHEFSONYA
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  • 31 POSTS
Does each injector have its own ground or are all the injectors on one ground?
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Tuesday, August 14th, 2012 AT 12:24 AM
Tiny
ASEMASTER6371
  • MECHANIC
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Each have there own ground but the ground is the pcm. You have a wire that is grounded before it hits the pcm.

Roy
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Tuesday, August 14th, 2012 AT 12:26 AM
Tiny
PCHEFSONYA
  • MEMBER
  • 31 POSTS
Would you recommend undoing the crossover pipe on the exhaust for easier access to the wiring and un-taping the wire loom and check manually the whole way or is there an easier way to track it down?
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Tuesday, August 14th, 2012 AT 12:30 AM
Tiny
ASEMASTER6371
  • MECHANIC
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Find the color of the wire and trace it every 2 or 3 feet. You will have to remove whatever is necessary to get to the wire.

Roy
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Tuesday, August 14th, 2012 AT 1:42 AM

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