Any chance you could snag a video of it? I know its kind of a pain to record these things but then you would have something to show the dealership (and us couch mechanics).
Some tips for this type of video:
- Try to record when there is the least amount of extra sound pollution around you from wind or highway noise etc.
- Try recording the sound at multiple distances, its hard to know at what point it will become clearest in a cell phone mic so getting a few seconds at 6 feet, then a few more seconds at 3 feet, and then up close, can help a lot to get lucky and find the magic point at which the phone mic picks it up the best.
- Having an assistant helps a lot, they usually end up having to run the camera so you can run the accelerator. Walking them through the shots you want to take BEFORE starting the car and recording can help make a concise video you (maybe) won't need to edit.
- If possible, do the noise video, then stop recording, go drive for 10 minutes or however long it takes for it to warm up and have the noise go away, then record the same shots with a warm engine so people can hear the difference and you can prove there is a distinct difference between warm and cold noise.
- If you bring the videos to show the dealer or a mechanic, bring some headphones because its probably not going to come through your phone speaker worth a crap. Review your clips ahead of time so you can show them the best spots quickly because they don't want to watch 20 minutes of your car running when only about 45 seconds worth of it is needed to get the point across.
I find this 4 banger to be a rather noisy and rough one as compared to others I have owned, surprisingly a lot of vibration sometimes when idling but oh well.