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2004 GMC Envoy rough idle (vibration at idle)

Hi Cart Talk Community!
I have a 2004 GMC Envoy w/130K+ miles that just went in for maintenance. One of the things my mechanic was fixing for me was a rough idle, vibrating strongly enough to rattle the mirrors and glass. He replaced a very loose and failing water pump, and I will say that the idling is better, but it’s still a little rough. The one problem was hiding another. Once I accelerate, no problems; nothing in park or neutral, only idling in drive. No CEL, no codes from the computer. My mechanic thought engine mounts might need replacement, but I thought I’d check what other smart-like car-folk may think. You know, a crowd-sourced second opinion.
Thanks!

If it doesn’t vibrate in park but vibrates in drive, jack up the engine slightly to get the weight off the frame. If it’s now better, then I would have to concur that the mount(s) need replaced. Not that uncommon.