Slight shake at idle

I have a slight shake that is felt in idle and it seems like it is more noticeable jn park vs when it is in gear. I don't think a motor mount could be the problem because I would imagine if it were a motor mount I would feel it all the time and not intermittently...also it would be more of a vibration feel than a shake and it would happen more in drive than in park....but maybe I'm wrong and weak mounts can produce my symptoms...

I have a cheap scanner that gives me mode 6 and does show misfires but not enough to set code and I have no idea when these misfires are even being recorded...

Car has great power and acceleration...I have new plugs wires and coilpack. Ignition is pretty much 100% ruled out. I am wondering what to do next as far as troubleshooting goes....it is either something not performance related (mount...exhaust mount...torque converter) or it is an ever so slight misfire that is enough to produce the slight shake at idle....fuel trims are perfect short term st idle and long term a little bit lean....bank 1 is around +2% and bank 2 around +6%

I really don't think this is a fuel/air issue so I'm about to rule out anything related to the fuel/air system and I am left with perhaps an engine that just had uneven compression or possibly intermittent valve issues that show up more at slow idle speed....

Potomus Pete said:

What about the balancer/crankshaft damper

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I have read about that but I frankly have no idea how to inspect it. From what I have read about it everyone seems to say that the vibration would get worse with rpms....

As far as what it looks like...it looks original....rusty....I can't see any rubber or would know where the rubber is even supposed to be? I heard something about painting on something white and revving the engine and seeing if it moves....

Could a bad balancer cause INTERMITTENT slight shaking?

I just went under there with the engine off and to my surprise I finally did find the rubber and it is dry rotted and cracked. I bet that it is enough to cause intermittent shaking at idle specially in park vs drive....in drive I feel like the torque from the transmission dampers it....when it is in park it is isolating the harmonic balancer more and making all the effort put on it to balance everything....

Thank you....I am thinking it might be worth actually replacing this part now. There is definitely some dry rotting and cracking of that rubber inside...

Potomus Pete said:

Shine a flash light and look for it being warped at all. I get under there while its running and just lightly touch the side. Not reccomended but it worked for me. Mine was off a touch

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Yours was off a touch....what were your symptoms? I just took a video and uploaded it to YouTube. It does appear to be moving in and out a little....that with the rubber cracking/dry rotting makes me think it needs to be replaced and HOPEFULLY after replacing it the shaking at idle goes away.