My 2017 Ridgeline has had a low rpm rattle under hood for almost all of its 40,000 miles. It is especially noticeable coming up hill in at a low rpm. Honda dealer has not been very helpful. The tech took a drive with me. I replicated the noise. He tried tightening the hood and the loose engine cover which I have since taken off. I left it with them and when I picked it up the noise shortly reappeared. There is no vibration associated with this. Any help would be greatly appreciated.