hour later very hard to start

1987 GMC SUBURBAN
260,000 MILES
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DRIVEWAYTECH
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  • 1 POST
87 gmc 454 new plugs ,wires,cap and rotor. started fine, idled smooth. hour later very hard to start. noticed green wire broken off sensor between two plugs(o2 sensor?) is this the problem?

no codes showing,fuel pump is functional,not sure of pressure,runs well once started,
Feb 11, 2012 at 11:29 PM
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RASMATAZ
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Check the fuel pressure if its within specs
Feb 11, 2012 at 11:30 PM
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RASMATAZ
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  • ASE Certified Mechanic
What about the green wire missed that one-
Feb 11, 2012 at 11:37 PM
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CADIEMAN
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if it runs great.then u get a draging start.youll need to check if a heat shield is missing or the timing maybe to far advanced.make sure your battery passes a load test and connections are good.
Feb 12, 2012 at 12:03 AM
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CCUPDAVE
  • MEMBER
  • 61 POSTS
That Wire sounds like it might be either a knock sensor lead or maybe the temp. sensor.
Good luck
Dave
Feb 20, 2012 at 5:59 PM
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