I dropped off my Infiniti SUV for an oil change and diagnosis of engine pinging (maybe) that I had noticed, plus occasional noise from the heater blower motor (that my wife had noticed). Hedman techs couldn't hear the noises on a test drive; so we'll try another day. In the meantime, I discovered that the blower motor noises were more noticeable when accelerating -- and were really what I had thought might be engine pinging. The "pinging" stopped immediately when I shut off the blower, despite continuing to accelerate up a hill. So the fact that they could not hear the pinging was exactly the right diagnosis, instead of a tune-up like I suggested might be needed. And Roy Hedman cheerfully topped off the air in my friend Ali's tires when Ali dropped me off at 5:29.
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