Intermittent fan max RPM

My macbook is having random spurts of the fan at max RPM. There doesn't seem to be much pattern, it'll stop and start randomly, often turning on right as I start up the laptop. It isn't an actual cooling problem, sensors are showing normal CPU temps, battery is still in good condition. The odd thing is, using Macs Fan Control the left fan (the one with the problem) is showing it's at 0 RPM. The right fan seems to be working normally.

I've already reset the SMC and PRAM. Seems like maybe a hardware failure or a bad connection, but is there anything else I can do?