[Foeux]

Originally Posted by Ian21401

Foeux,
I’ve been following this thread and it has me intrigued.
Just a few thoughts from an outsider. Feel free to ignore them if you wish.

Post #26, When you first tried the engine would not turn over. Did you check the battery voltage before you tried to start the engine? To try to establish whether the battery voltage was already too low, or 1) it suddenly dropped once the ignition was switched to position 1, or 2) it suddenly dropped when the switch was in position 2, or 3) it suddenly dropped when the starter motor was trying to turn?

Once started using a jumper battery the alternator is charging.
I understand that you then disconnected the jumper battery?
and then after a few minutes of running on it’s own battery the engine dies?

You mention that the charge rate was dropping after the engine stopped.
As the engine was now stopped there would be no charge from the alternator so, do you mean the battery voltage was dropping?

Is it possible to state what the battery voltage dropped to before you switched off the ignition?
Yet, when you switched off the ignition the battery voltage returned to 12.24 volts.
Given that the engine would not turn over when first tried this morning. Is it possible once the engine has been running then died to check the battery voltage periodically to establish at what rate the battery voltage drops?

I am very pleased for your input. To clarify, the battery 'heals' itself back to 12.32v if left long enough. With key in position 2, the voltage drops rapidly to 9.2v which happens over the course of 2 mins. I know this as I was testing earlier to see if I could make the voltage drop slow or stop by pulling fuses to identify the bad circuit. Alas I could not but interestingly it seems to stabilise at about 9.2v in pos 2. As soon as you try to start it, the voltage drops madly to 3v ish as you turn the starter. The car is then 'dead' or at least in a condition that might start with a jump. The most recent serious stop, it wouldn't even start with a jump UNTIL it had been towed and waited a while, whereupon it started - could this be a loose wire thing?

Now that I have left the car from its original state of unwellness, it has 'healed' the battery back to 12.29/12.32v. Turn the key to pos2, it will do it again.

Originally Posted by griston64

Your battery is charging ok when running ( should be between 13.7 to 14.7 ) but it's dropping too quickly and not holding the charge.

I'd be wondering what's making the car splutter and cut out after running ok for 5 mins ?? Surely thats still going to happen even with a brand new battery ?

This is what I wonder and why I am so keen to diagnose instead of fire the parts gun at the car: New battery, alternator and starter and cables might not fix it and I have then chucked out good volvo parts, only to replace them with inferior newer ones that will wear out quicker.


As for the battery calcium/silver thing, surely the car is dumb as bricks?

If there were a small nuclear reactor generating the correct voltage, would it 'know'?

PS I have just been and started car, helped it get through rough running phase and wanting to die by keeping revs up. Seems ok now and will restart under own battery power. Am I stupid to think that water could be in somewhere and evaporating to the point where the car shows no fault once the heat of the engine drives moisture out?