Battery/Alternator Question which one?

Discussion in 'Other Automotive Tech & Talk' started by lngroller, Aug 19, 2008.

  1. lngroller

    lngroller Member

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    My 96 e150 van is having a problem. when driving it reads about 12.2v when running about 14.6v (as checked this morning cold)Last night, the in van volt meter read about 12 v while driving but dropped to about 8-10v when idleing. I was able to make it back abot 90 miles in the dark with lights and radio, GPS on so I think the Alt must be charging? but why the batt. drain? As a Battery warms up, could it be that it stops taking a charge? If bad that is.

    I expected this morning to get a 12v or 11v reading with van running this morning, and a stopped v even lower,but I guess the batt. rejuevenated overnight.

    I would have assumed Alt but I just replaced it about 3 mos. ago. The reason I am still not sure is that NAPA had to go through 3 before they found me a good one. (I had them tested before I left)

    So, Batt. or Alternator? or could there be something else I'm not thinking of?
    The Volt readings this morning were taken with a Multi meter at the battery, not the in dash guage
     
    lngroller, Aug 19, 2008
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  2. Andysutt

    Andysutt '72 Comet GT

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    Maybe your in dash gauge is screwy?

    If the volts check out with the engine off, and running, then everything should be ok.
     
    Andysutt, Aug 19, 2008
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  3. lngroller

    lngroller Member

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    change happens as it warms up

    Ok, everything read correctly (both at battery with volt meter and with in dash volt guage) when cold. 2 miles later guage starts getting screwy again so I pull over and put voltage guage on battery with engine running. Now I only have 12.4 v from alternator.

    It is not the guage because when it is acting up the tranny also shifts funny. Alt checks ok and Battery has been replaced ( it was old anyway) same problem persists. where do I look now?
     
    lngroller, Aug 20, 2008
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  4. PaulS

    PaulS Member extrordiare

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    Start with the connections to Ground. They should be as large as your battery cable.
    Next check all the cables and connections to make sure they are clean (shiny) and tight. Check the belt to be sure it is in good shape and tight - slipping belts will lower the charge rate of the alternator and they don't always make noise when they slip. Check the pulley on the alternator to be sure it is tight and not slipping. Check the fusible link or fuse on the alternator to battery cable for corrosion and tight connection.
     
    PaulS, Aug 20, 2008
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