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Well, I thought it might be a few years before coming to a forum to seek some help! I currently have a 2019 GMC Sierra SLT with 4x4, standard box length, 6.2L engine with tow package added, at around 20000kms (around 12K miles?) And I have been running premium fuel in that beast since day one. My engine made a few pinging noises one day while going up a small hill, then the MIL engine light came on. It hasn't made those noises since. I took it to the local dealer to scan, but the first time they took it in, they did a programming upgrade (recall) to the computer before scanning it for codes, so it erased all history and cleared the MIL engine light. About a month later, the light came on again, no engine noise this time. I took it back to the dealer, due to COVID regulations I couldn't be in the vehicle when they scanned it, so that service advisor cleared the light and codes. (Double piss-of now) It came on a third time, after 2 weeks since it cleared and it was the Knock sensor again.. This time I wouldn't leave the truck while they diagnosed with the scanner. Code: P0328 - Knock Sensor Circuit High bank 1 It has been in the shop now for 4 working days, and the advisor called me today: -They took a fuel sample and sent it to the lab for GM to confirm I had been running premium fuel in the truck. -They believe that there may be a "parasitic draw' on the wiring harness from the ECM to knock sensor -They found lower than normal voltages at the knock sensor -They have wait to be advised by GM Canada to go ahead to replace the wiring first, then the knock sensor and the possibly the ECM if the lower voltage doesn't rectify Yikes... Would a faulty knock sensor cause pinging in the engine? Apparently with this model year and config there has been two vehicles previously exhibiting these conditions. One was from an individual running a higher than normal ethanol blended, lower octane fuel. The other had wiring harness issues. Apparently there is no specific TSB related to this exact issue, although wiring harnesses seem to pop up in question in other threads. I will keep the thread updated. Any insight appreciated. Cheers, Andrew