Hey guys,

So I have a shudder at idle and when reved in park - its an Auto. Harmonic balancer looks fine. Also shudders under accelleration. No missfires that I can here. The shudder is worse between up to about 2000 rpm. IS Valve maybe?

Welcome any thoughts!

I thought maybe harmonic balancer, but it looks pretty solid.

I also disconnected the IAC and started her, she idled low, reconnected while running and revs came up immediately so I dont think its IAC.

Update: Replaced all the spark plugs, leads and coils. So I can take that off the list. The plugs were RS. So while its got more oomph now... still have the vibration.

Currently thinking either balancer (which looks ok, but is rusty) or engine mounts.