comet running rough (help)

Discussion in 'Technical' started by mavmike72, Oct 5, 2008.

  1. mavmike72

    mavmike72 Member

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    Last night, msd cap and rotor. Im just wondering i keep putting in old injectors that my buddy has maybe i need to buy all 8 new ones. Only thing is i hat to invest that kind of money and it not fix it.
     
  2. blugene

    blugene Senior member Supporting Member

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    Some one already mentioned to swap it to a different location to see if the problem follows. If you don't have a missfire anymore than what are you chasing?
     
  3. Mavman72

    Mavman72 Gone backwards but lookin' forward

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    If you replaced any of the other injectors with used ones. I would start with them.Ohm them before you go bying newbies,check for pulse at the other injectors.Prove out what you have before you throw money at it.
     
  4. Mavman72

    Mavman72 Gone backwards but lookin' forward

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    You have had that plenum off a bunch of times too.Are you positive you dont have any vacuum leaks???
     
  5. mavmike72

    mavmike72 Member

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    The serging. When we put some in the other day we thought they wre spraying but last night they wernt so we put other one in. Heck man i dont no im all out of ideas.
    Just like earlier when i left it ran great but then it starting running like ----.
     
  6. blugene

    blugene Senior member Supporting Member

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    What do you have for a fuel system?
     
  7. Mavman72

    Mavman72 Gone backwards but lookin' forward

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    Is this car you only means of transportation?? If not...Mike... leave it till tomorrow.Frustration makes ya chase your tail and second guess yourself.Leave it be,go back to it tomorrow with a fresh perspective.Re-trace your steps,your allmost there with it...only one problem left to solve.:yup:
     
  8. mavmike72

    mavmike72 Member

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    we ohm them first then cycled them first before bolting down the fuel rail. I friend just called me and said something about the temp sensor in the front of the intake. He said it might be bad because when i let it was cold and then it got warm. What do you all think about that ?????????????
     
  9. mavmike72

    mavmike72 Member

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    I have a msd 60 lb fuel pump. no its not my only car just drive this on week ends......
     
  10. Mavman72

    Mavman72 Gone backwards but lookin' forward

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    coolant temp sensor will cause a rich/lean condition if its malfunctioning,you may have a lean condition due to a bad sensor.I think that one should read low resistance when cold and high when at operating temp(ohms)if its reading high cold or low hot its not working properly.
     
  11. blugene

    blugene Senior member Supporting Member

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    That is something to look at.
    Going back to the alternator, just cause it is charging don't mean that the diodes are good... just a thought.
    Ok. What is your fuel pressure supposed to be at the rails?
     
  12. mavmike72

    mavmike72 Member

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    35 and we put a gauge on to see and it ok. So what other way do you check the alternator ?
     
  13. Mavman72

    Mavman72 Gone backwards but lookin' forward

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    You can get the alt tested at a parts store that does it(many do)or you can check the AC voltage output on it...if it puts out more than .9 volts AC, its bad.
     
  14. blugene

    blugene Senior member Supporting Member

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    Something like that... I think it's almost time to hook it up to a analyzer. Only a profesional who knows how to interpit #s may be able to find this one. Codes only tell you so much. Most times you get lucky and replace a part it says is malfunctioning, but sometimes the basics are causing it to go off. Not that it has in this case cause I havn't read anything aout a code. Just thinking and talking out loud cause I used to analyze but it's been a long time.
     
  15. blugene

    blugene Senior member Supporting Member

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    Intresting... hadn't heard this one. Is this test done at home? I was talking diodes by the way...
     

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