Originally Posted by Cab_Burge
The alternator regulator will make the alternator charge more when the engine first starts due to the drain on th ebattery from the starter turning the engine over and making it start, with the belt tight the alternator will put out over 12.75 VDC idling, it may only put out less than the minimum voltage the ECU has as it cut off voltage at idle with the motor warmed up with a loose belt work shruggy
A quick check with a decent voltmeter will tell you if that is the case or not shruggy scope


The part I am having trouble with is why the battery which should be at ~ 12.4- 12.6 won't keep the car running, but will start it powering both the starter and ignition, during which time the static V will drop to 11 or so volts due to the amps drawn by the starter.
I am not disagreeing or wanting to start an peeing contest but rather understand how low alternator output at idle makes the motor die but start right back up with less available V and I from the battery than was available when it died confused shruggy beer

If their are other large draws on the system BOOM BOOM STEREO, 50+ Amp fans and A/C Then it might make a bit more sense. Way back when, one would toggle switch the field connection off at the drag strip to take the drag off the motor wink
thanks for trying to make a hard headed pollock understand the above beer

www.tandmautomotive-omaha.com