As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) AIRCRAFT TOOK OFF AND THEN PILOT RETURNED WHEN HE NOTICED THAT THE LT ENGINE EGT WAS FLUCTUATING. RUNUPS WERE CARRIED OUT BY MAINTENANCE AND CONFIRMED THAT WHEN THE SHORT HARNESS WIRING WAS WIGGLED THE INDICATION WOULD FLUCTUATE. CONTACTS WERE CLEANED AND WIRING SECURED. NO OTHER FLUCTUATIONS HAVE BEEN NOTICED SINCE .