I'm having nerve conduction tests for carpal tunnel. Couldl the same test show guyons tunnel syndrome?

Possibly. Depends on how detailed the neurologist or other physician is in performing the emg/ncv's. If your referring physician explains the need for testing the ulnar nerve in guyon's canal it can be done... In my experience most ' routine' EMG 's of the upper extremity will note conduction 'slowing' @ the elbow( cubital tunnel) but not @ the wrist... Best of luck!