More Will It Start?

Today I took the 944 on a longer series of errands. I drove it over to Mill Valley where I went to the post office, and let it sit for about 10 min, it had a bit of a pause before it turned over, then to Muir Woods and let it sit for an hour+ and it started OK, then to the gas station, where it had a bit of a pause before it started, then to Novato, where I let it sit for about 30 minutes+ and it started right up, then to some guys house to pick up a part for my bro's jeep, where it sat for 10 minutes or so, and started right up, then to a friends house, where it sat for a couple hours and started right up. Another pass, but I still don't trust it.

I brought a set of jumper cables, and tools to clean the battery terminals...