Funky battery issue? Car shuts off while driving
08-08-2009, 06:34 PM
#32
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to eliminate the alt problem, start your car and take off your negative terminal while your engine is still running, or with a voltmeter check to see if you have 13.5 - 14.0 volts a little bit over by a few points or under is fine but if you drop under 13 and over 14 alt should be replace. an overcharge battery is worse then an undercharge one, i witness a battery explode during a diagnostic test on a customers car. similar problem to yours. but there are so many factors to your problem. i might be able to help.. all i need to know is do your engine cranks over or not when you say it wont start.? and we can go from there to eliminate some of the possibility.. o yea and you said it's boosted.? what kind of fuel pump are you running.? internal or external pump.?
08-09-2009, 02:06 AM
#33
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If ya have pulled the battery out of the car,then u probably noticed if any on the cells were low.Low cell and testing/charging and the battery can arc inside and boom.Could be the igntion switch with that big wad of keys u said u had.I've heard if ya bump the ignition key with your knee it will shut off will driving but should start back up 
Multimeter on the car running,like the man said, should tell u if it is charging.
Multimeter on the car running,like the man said, should tell u if it is charging.
08-09-2009, 10:57 AM
#35
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Yes, motor cranks all day just won't fire. Already replaced the ignition switch. Fuel pump could be it but honestly, all this started after I had let the car sit for 2 months and battery makes more sense than fuel pump. I think I may ask if I can borrow a known running battery and swap it in. If that doesn't start the car, It'll probably be fuel pump from there. If that doesn't work, I'll have to tow it to my tuner (about a $350 tow 
) and see if something with my AEM needs adjusted but I don't think it has anything to do with my map.
) and see if something with my AEM needs adjusted but I don't think it has anything to do with my map.
08-09-2009, 03:17 PM
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check for spark and fuel. no spark or fuel check your ECU, and was your gas tank almost empty when you had it park.? some after market fuel pump cant sit dry for too long it'll go bad, and if your always driving on low gas level it will also burn them out. and fuel pump can also be loose, i had a buddy that had the same problem with a walbro fuel pump, car will shut off and will turn back on when it wants to, sometimes right after it turns off you can fire right back up, sometimes he has to sit and wait. to find out that the connection was loose on the pump inside the tank. also if you have a good flowing fuel pump you should be able to hear it prime when you turn on the key, and you'll hear the relay click, under the driver side. even if the fuel pump dont work you should be able to hear the relay, i can almost guarantee its not the battery. sometimes you'll have a bad relay, it'll work till it overheats and it'll trip.
08-09-2009, 03:24 PM
#38
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Originally Posted by bAyaSsaSsiNs,Aug 9 2009, 03:17 PM
check for spark and fuel. no spark or fuel check your ECU, and was your gas tank almost empty when you had it park.? some after market fuel pump cant sit dry for too long it'll go bad, and if your always driving on low gas level it will also burn them out. and fuel pump can also be loose, i had a buddy that had the same problem with a walbro fuel pump, car will shut off and will turn back on when it wants to, sometimes right after it turns off you can fire right back up, sometimes he has to sit and wait. to find out that the connection was loose on the pump inside the tank. also if you have a good flowing fuel pump you should be able to hear it prime when you turn on the key, and you'll hear the relay click, under the driver side. even if the fuel pump dont work you should be able to hear the relay, i can almost guarantee its not the battery. sometimes you'll have a bad relay, it'll work till it overheats and it'll trip.
Good info 
08-09-2009, 04:07 PM
#39
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Originally Posted by bAyaSsaSsiNs,Aug 9 2009, 06:17 PM
check for spark and fuel. no spark or fuel check your ECU, and was your gas tank almost empty when you had it park.? some after market fuel pump cant sit dry for too long it'll go bad, and if your always driving on low gas level it will also burn them out. and fuel pump can also be loose, i had a buddy that had the same problem with a walbro fuel pump, car will shut off and will turn back on when it wants to, sometimes right after it turns off you can fire right back up, sometimes he has to sit and wait. to find out that the connection was loose on the pump inside the tank. also if you have a good flowing fuel pump you should be able to hear it prime when you turn on the key, and you'll hear the relay click, under the driver side. even if the fuel pump dont work you should be able to hear the relay, i can almost guarantee its not the battery. sometimes you'll have a bad relay, it'll work till it overheats and it'll trip.
Thanks for the info, I'll try that before I replace anything else!