Misfire and Weak Battery

[DrRobin]

Thanks for the quick reply.

I have a CTEK Battery Sense fitted, this records battery coltage and temperature every couple of minutes and works out charge level. The battery was showing as 10% charged at the time.

When the misfire occurred the voltage shown on my in car voltmeter was 14.1V, but then that averages the voltage, so there might have been short term dips, I.E. when the coil or injector fires, especially if the battery was low, the battery internal series resitance could be high and this would limited the size of current pulse. The alternator might have too much inductance to supply short term high current peaks?

I had a new alternator on about 5 or 6 years ago, this one looks like it is charging, but I don't use the car much and it's only 10 miles to work, so the battery doesn't really get much put back in.

I have a battery/alternator tester, I will put this on at the weekend and see if the alternator is charging correctly.

I have a CTEK maintainer, but the car lives outside and it's not practical to leave it plugged in all of the time.

I just wondered if others had seen something similar or if it was a known problem?