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HELP diagnosing this problem

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Old 03-11-2009, 05:58 PM
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HELP diagnosing this problem

Okay... My truck is all sorts of messed up. I stopped at wal-mart after work to pick a couple things up, and when I started my truck to leave, I noticed that my stereo lost all it memory, like the battery was disconnected.

So I start driving down the highway, and as I give it some gas to pass someone, my truck starts bucking like crazy, I look down at the guages and the rpms are jumping from 3 grand down to nothing then back up again. Check engine blinks on everytime the rpms fall. Drove just fine when I wasn't stepping on the gas too hard.

I got it home, and jumped out, went to push to lock button and I have no power again. So I need some idea of what is going on here. I put a new alternator in last weekend, so i'm guessing it's got to have something to do with that.
 
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Old 03-11-2009, 06:01 PM
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The connection at the battery is most likely bad. Best case you pull the connectors off, clean them and are good, worst case you need to replace at least the positive cable. You could very well also have a bad battery.
 
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Old 03-11-2009, 07:57 PM
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Father in law cleaned the posts and connecters while I was putting the intake back on, maybe he didn't get it on tight.. otherwise i'll try replacing the cable. Thanks!!
 
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Old 03-12-2009, 05:50 PM
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If the connections were found to be tight,Id take the "new" alternator back and have it checked.If it was a reman,this could easily be the problem.ESPECIALLY if it was from Autozone.The batt of course could be defective,but i still "smell" alternator issue.
From what it sounds like,the alternator is not doing its job causing a low-voltage condition.....if you think about it,the faster you wish to go,the more electrical capacity it takes to fire the plugs....conversely,the slower you go,the less demand on the system.Most automotive ignition systems will not function properly under about 9 volts DC.Needless to say anything lower than that value will result in weaker spark,and overall ignition system failure under load.The radio situation also points to this since the radio memory is stored by a DC voltage thats constant to the radio(even when the vehicle is parked)....I mentioned Autozone reman units for a good(as far as Im concerned) reason..I had to take back THREE alternators before I got a "good" one....This wasnt for a Ford,but I still have serious concerns about their "contractors"....
 




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