With the colder weather upon us (well, at least down south here, in Victoria!) and driving to, and from work each day with the headlights on, I've started having 'power' issues. I thought my tiny little 4-year old battery was well... past it's use-by date.
The car has been getting progressively, ever-so-slightly harder to start, and on Sunday, I had been driving for about 20 minutes when, I pulled up at a set of lights and the car just stalled. Trying to re-start the car, it just went "no-oo-oo-o p e ...."
I got my brother to pay me a visit and a jump-start got me home, where I put the little battery on charge straight away.
So I popped into our local 'battery world' outlet this afternoon (where I bought the battery 4 years ago!) with the view to replacing it.
The ever-helpful guy wheeled out a gadget with two dirty great big analogue meters on it, a dial in the middle, and jumper leads the thickness of my thumb attached.
He connected the leads onto my battery, and dialed up some load on the battery. He was surprised to see the meters reporting that the battery was still supporting the battery's designated full load. Declaring the battery fit for purpose, he then checked my alternator output. It's putting out plenty of juice, so he was a bit stumped as to why I might be having power issues. He took another, closer look at my battery terminals, and suggested I pull them all apart and brighten them up with a wire brush...
15 minutes with a brass wire wheel in a battery-drill had every face of every contact shiney and new.
Bolted them all back together again and made sure they were firmly snugged up.
Jumped in the driver's seat and turned the key. Holy Crap! The motor nearly jumped out of the engine bay it started so fast! And idles like a dream now too...

Happy camper. Best 15 minutes I've spent on the boy in ages...
Don't believe me? - try it yourself! - You won't believe the difference.