Then I'll put $0.02 on a cracked flex pipe.

 

That will be very telling... vibration goes away, problem probably an accessory pulley or tensioner. Vibration persists, harmonic balancer, torque converter, flex pipe, or... I hate to say it... something internal. Although You probably wouldn't be saying it runs great if it were internal.

 

Here's my latest update on the vibration . Removed serpentine belt and started the car , vibration did not go away, so it's not the alternator, compressor or tension pulley . The rubber on the harmonic damper is not rotten and seems to be in good shape , All the pullie's are tight , the down pipe is solid with no cracks . I have not checked the torque converter bolts yet.

 

 

Torqued everything down and found nothing loose , I had recently replaced the top motor mount (looked bad) and replaced the 2 bottom transmission mounts (did not look bad), it did help a little with the vibration , BUT I had not replaced the drivers side mount , so I removed it and it looks bad . I also decided to start the car with it off and it feels exactly the same as if it were on ! I will try and find the part tomorrow , hope this is it .

 

Interesting one - let us know how it works out once that drivers side mount is replaced.

 

If you can't see the motor vibrating it shouldn't be mounts, it almost has to be internal.

 

Quick question, has the water temp been normal/ok??

Reason for asking is that the water pump and balance shafts are all run from the same chain assembly... A slip or jump of that chain could certainly cause a vibration. If you can't find the issue externally, you will need to go internal.

 

I'm with Donbrew and Doc on this one. Replacing the drivers side trans mount probably isn't going to correct the issue. If the mount was bad, it wouldn't shake any more than if it was brand new. Which is what you described... It's actually quite a weak mount, it is flexible both horizontally and vertically. The coolant temp would be what I was looking into.

As Doc said, if the balance shafts are out of time, they'll cause a lot of vibration. That's why they are there in the first place. They spin at twice the RPM of the crank. I've ridden in an LNF with the balance shafts out. It's enough to rattle your teeth. And if I remember correctly, it was right about 2000 RPM.

- my guess it's internal, unfortunately.

 

Water temp is normal . I"ll replace the mount because I have it off and it's pretty obvious its bad . I'm not expecting it to solve the issue . Can the balance shafts be put back in time if this is the problem ?