Weak cranking - partially resolved
 

Did some work on my car so I felt the need to drive it around for a bit and enjoy it. Tried cranking it over and it was really slow & weak, acting like a low battery. Checked my battery cables (tight & no corrosion). Threw on the battery charger and put it on jumper mode and cranking still the same.

Got underneath the car to check the starter and the black wire w/ red stripe (I'm guessing ground) was connected, but not fully tight on the spade terminal. It looks like the plug is not keeping a tight connection and wiggled itself loose to cause the weak signal. I pushed it on all the way, and car was cranking normally.

I couldn't really see a way to tighten the connector, so I'm guessing the best way to fix it long-term is cut the old connector off and put a new one on?

That little black/red cable isn't a ground, it's a switched 12v source from the ignition key to the starter solenoid. Connection their needs to be tight and clean otherwise the solenoid doesn't activate the starter motor correctly.

So it would be best just to cut off the old connector and put a new one on?

If it slides off very easily then yes. You may also be able to compress the black cover with some pliers a little bit to compress the inner tongs closer together.

I thought about that but figured the plastic would crack like all the other plastic on our cars. I looked at it again this morning and doesn't look like enough slack to cut & crimp a new connector. I might have to crimp a new connector onto some spare wire and solder it onto the old.