I ask this here because I value the opinions posted on this forum. My wife's 98 Ford Escort (gasp) starts intermittantly. It was stored in a heated garage for a short time with and I put a battery tender to it every couple of weeks or so. The terminal began to corrode heavily. I checked juice at the battery and had 12V+. At that time it was giving me probs starting so I replaced the terminal ends and found that one was cracked/broke. Problem solved so I thought. She ran it again today and it started fine this morn. It failed to start after she stopped at the bank. It just clicked. I checked V again and was getting 12V+. When we jumped it, it started right up. I checked V again while running and got 13V+.
So the charging system is working. Do I assume that the battery is bad (original) and replace? Does the heavy corrosion at the terminals indicate a bad battery?
Because I am getting 12V+ doesn't mean the battery is delivering the full CCA?
Starter maybe?

__________________
'85 300SD (formerly california emissions)
'08 Chevy Tahoe
'93 Ducati 900 SS
'79 Kawasaki KZ 650
'86 Kawasaki KX 250
'88 Kawasaki KDX200
'71 Hodaka Ace 100
'72 Triumph T100R