My car died on me but its not dead HELP!!!!!

[MercNasty]

So i was heading home last night after driving the car to and from work when all of the sudden the battery light flashes and then the car shuts off on me while i was sitting at the light. The car starts and right when the RPM's start to go back down the car shuts off. I couldn't get it to turnover so i had to call a tow. My LED battery terminal is only reading 12.0 and its usually at 12.5 or higher. I just bought the battery last year and I had the alternator rebuilt last year. Ive been scratching my head trying to figure out what it could be so I figured i would come here as always before i start taking everything apart. Please give me your thoughts as to what the prob could be or what I should check. Thanks in advance.

ken

[Spectragod]

Bad ground
Bad Positive cable
Bad alternator
Loose cables
Corrosion on cables

Could be a # of things.

[Gryphonzus]

It could also be a bad battery. I purchased a brand new battery and it was bad. Got a replacement and it worked fine.

[fastblackmerc]

+1 on all of the above.

[babbage]

Bad ground
Bad Positive cable
Bad alternator
Loose cables
Corrosion on cables

Could be a # of things.


^^^ What he said! Did you get a motorcraft battery?

[ctrlraven]

Bad ground
Bad Positive cable
Bad alternator
Loose cables
Corrosion on cables

Could be a # of things.

Any of those would be my guess.

Have to watch rebuilt alternators 4 out of 5 times they end up having to be replaced soon after installing them, which is why most come with a lifetime warranty.

I would start with checking all connections, if those are good move on to the battery. Check the fluid levels in the battery and add if needed then charge the battery up. If it still does not work or won't stay running then most likely it's the alternator.

[MercNasty]

Thanks for all the replies guys, I know it isnt the connections, I have already checked all of them. Tomorrow im going to take the battery out of my other car and put it in the Marauder, im hoping its just the battery. If its not the battery then Ill swap out the Alternator and put the one i bought off line in. The battery I have is a Napa legend. It i find out it is the battery, I will get a refund or store credit for that one and go with a different brand because this will be the 3rd time having to swap the battery out. I will keep yall posted. Thanks again.

[BlackJack]

3rd time swapping batteries sounds like a bad alternator to me. I would recommend putting in the spare battery and if it runs, take it to Autozone and have them put it on their charging system test machine for free. FWIW I've had excellent luck with NAPA batteries...

[ctrlraven]

A low charge alternator can kill a brand new battery.

When I bought my MM it had a low charge alternator (12.2 volts at idle with everything turned off), had the dealer replace it and it has been charging 14.1 volts to this day after it was replaced.

[RF Overlord]

My LED battery terminal is only reading 12.0 and its usually at 12.5 or higher.It should always be at least 12.6 open circuit (no load) when fully charged. Yes, tenths of a volt do matter.

While charging, the voltage should be between 13.2 and 14.4. It will be at the higher end of the range when the battery is low, and at the lower end when the battery is fully charged.

[MercNasty]

so after swapping batteries and alternators, i found that my JLT CAI was not connected to the intake. After re-connecting it, the car started right up. I put the NAPA battery back in and the rebuilt alt and it started right up. So the problem all along was the CAI being disconnected. The rubber piece keeps sliding off the intake no matter how tight I have the cable tie screwed. I think I will buy some new cable ties tomorrow if it still slides off, i may need a new rubber piece for the JLT.

[marauder410]

K&N CAI FTMFW :argue:

:lol:

[BlackJack]

I had that problem on a Mustang-car usually ran like crap before the CAI came completely apart. Glad you found the problem!

[fastblackmerc]

You should have stainless steel worm clamps on all the connections.