to make a quick check -- start car - disconnect the positive cable at the battery as it is running - if car stalls the alternator is bad if it stays running the battery is probably too weak to hold a charge. (daddmac)
Likely the battery or alternator, but probably the alternator
I have a 1993 silverado that was doing the same thing, and the problem turned out to be a bad regulator inside my brand new alternator. Ireplaced it and went ahead and replaced the battery, I haven't had the problem since! Hope this helps. I have a 1993 silverado that was doing the same thing, and the problem turned out to be a bad regulator inside my brand new alternator. Ireplaced it and went ahead and replaced the battery, I haven't had the problem since! Hope this helps.
The battery is basicly used just to start your vehicle, the alternator is what generates your power once the vehicle is running. Which indicates you need a new battery, not an alternator. That is why you problem goes away after a jump start(boost). If it was the alternator the problem would not go away and your vehicle would have no lights and stall with no start. Either your battery is bad or the alternator is not charging.
check your alternator it might be bad.
We had this problem. It turned out that moisture had gotten into the distributor cap. Once we replaced it, the problem stopped! I had the same problem with my 93 Ford Tempo and after Sears had replaced the battery, they did not completely tighten down the ground cable. Ford could have put a better battery terminal on the car as well, as it was a bear to tighten down.
Have the alternator tested.
Does the Alternator have a power supply back from the battery to excite the alternator? I had the same problem and despite trying several alternators found that a fuse had blown on the circuit bring power back from the battery. Or the bushes in the alternator could be worn out or the diode pack could be shot. Put a volt meter onto the small wire on the alternator and across to the vehicle body you should have battery voltage on this terminal.
If the battery is less than 2 years but doesn't seem to hold a charge
Check battery connecters to see if they are tiightly connected. I had that some problem and it was the old battery connecters that where loose. I brought some new connecters and had the mechanic put them on. never had a battery problem even sense.
Disconnect the battery. Remove the alternator belt. Disconnect the wiring on the alternator, then unbolt and remove the unit. Bolt the new alternator in place and connect the wiring. Install the belt and connect the battery back up.
Your alternator might be bad and not charging your battery properly.
if a battery has a bad cell it wont hold a charge, but it could also be the alternator or the plug, i had a problem with the plug and had to change it from a junk yard, but before you do that i would check the easy parts first i.e the battery,then the cables, then the tension of the alternator belt, and finally the alternator itself along with the pigtail get a volt meter and test the current while the car is running, if it reads 13 to 14 volts the alternator is working and if it reads bellow 12 it is the alternator or plug. aojedamCheck your battery, it might be worn out and not able to hold a charge from the alternator.