tim bones

Need Help With Alternator Diagnose

11 posts in this topic

have new battery and this morning my car was totally dead no power.i jumped it got it running but if i put any power on it stalls.i did start hearing a wining noise yesterday near the alternator.does anyone have any input..

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Measure the voltage on the battery with it off and on.

 

Off if it's < ~12.2 volts, the battery needs to be charged.  If on it's not at least 14V or so, your alternator is probably dead.

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Hey snailman thanks for getting back to me! As i have read from other 626 owners there alt. belt squeals.Before my friend attempts to change my alt.in this cold,i was wondering if the belt had a little slack(1/2 inch) in it would that cause my problem mimicking the bad alternator.After i jump it to start it the battery is 12.4volts.Another words should i try and tighten belt first or am i wasting my time.

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Measure the voltage on the battery with it off and on.

 

Off if it's < ~12.2 volts, the battery needs to be charged.  If on it's not at least 14V or so, your alternator is probably dead.

i replied to you in the wrong section.read my post at 12:41am.

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Proper belf deflection for the FS alternator belt is about 7-9mm.  0.25-0.39 inch.  You want it closer to 1/4 than 1/2.

 

Here's a belt diagram for the FS and KL engines that shows belt tension (measured in lbs) and belt deflection (measured in distance).  Unless you have a belt tension tool (99% of DIY'ers do not have this tool) then just about everyone goes by deflection measured in distance.

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If it's 12.4 volts after starting, and your alternator is spinning (and the belt isn't squealing when you measured it), then yeah, sounds like your alternator is toast.

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last week i changed my alternator.I thought that was the problem and everything was fine until today.The car wouldn't start.So i jumped it and it started but while driving to get home i noticed the gauges jumping around when i would put some power on like the the heat.And also i noticed that it wasn't shifting properly like it was stuck in one gear.Does anyone have any input on this..

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Which gauges?  Both the tachometer and speedometer or only the tachometer?  Tachometer jumping means a distributor issue.  Speedometer jumping means a Vehicle Speed Sensor issue which can cause a lot of other issues especially for an automatic transmission.  Someone else recently posted that they feel like they are in 5th gear and the car barely moves when giving it a lot of fuel. That could be fuel pressure related and might have gauge symptoms to go along with that.  It could be alternator related since a jump start helped you out but you still have to do some basic diagnostics and process of elimination before you know which direction to head.

 

Start with the basics.  Check for good spark and fuel pressure.  Recommend you watch some youtube videos on how to do that if you've never had to do it before.

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both gauges were jumping.And i noticed the temp. gauge was lower than normal.I just put tester on battery and it's only reading 10.5 volts in off position .My neighbor thinks it might be a ground.Is that possible?

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Definitely possible.  Sounds like an electrical connection issue either at the battery, alternator, or fuse box.  When the gauges jump does the lights flicker on the HVAC controls and radio? 

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I didn't notice if lights flickers because of daylight.But now that you say it it was hard to see if the car was in drive on the dashboard light.I just had the battery charged and checked it at auto store.It came back good.it said voltage was 13.23..The next thing i'm thinking of doing is looking online for maybe ground diagrams.I really can't do much outside because of the cold.The salt they put on the roads around here definitely could corrode the cars wires.Not to even mention the pot holes are like craters.If anyone has any links for me to look at about grounds or wiring please send them..

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