Well, I have always used REGULAR gas, despite the fact Mazda recommend Premium, and never had a problem with pinging, except very occasionally if uphill in too low a gear. But I could try changing to Premium. Not sure what OEM is, but all the new parts came from the Mazda Dealer.
What part would you change/adjust to get the EGR back in range? Is there an EGR Circuit that could be changed/fixed? I guess I could also have a tune-up.
BTW, for readers' reference: I found the Trouble Codes conversion
Friday, October 5th, 2007 AT 2:34 PM