Newbie Tacoma engine question

I bought my 2014 Tacoma 3 months ago. It's a V6 27000 miles. A week after I had it I notice after the engine warmed up it would diesel (ping upon excelleration) Ivery had it to the dealer 4 times. They replaced a bad cat then they did a flash and updated the computer. It resolved it for a week and a half then went right back to the way it was. Toyota engineers are on it now saying this has never been heard of. But I've seen alot of complaints on different sites about it. Does anyone have any helpful info on this matter. I'm worried I made a mistake buying this $28000 truck that is still at the dealership in the garage.

 

Welcome to TW!I'd post this in the 2nd gen.section of the forum!Probably get more attention or resolve!