My Honda City has "pinged" under load from the day I bought it two years ago. The service people will not even acknowledge that it does it, and seem totally disinterested. How can I have my car serviced by a non-Honda company and not affect my warranty?
You don't say what fuel you have been running it on, but if you've been using regular unleaded try a higher octane rating fuel, such as 95 PULP or even higher 98 and see if the pinging goes away. You can have your car serviced by any qualified mechanic without affecting the warranty, as long as it is done according to Honda's recommendation.