My car "vibrates" at 2000 RPMs. Everywhere else it runs fairly smooth. It has good power right up to wherever I decide to shift (usually about 5800 RPMs).

It does it when its cold and when its warm and even does it at no load. And it does it with the MAF unplugged.

One other wierd thing: upon deceleration, BANK 1 BLMS are around 115, while bank 2 BLMS are up near 135. Under acceleration they are generally closely matched, but in the mid to upper 130s.

Any ideas as to what is likely causing this?

 

Could be a misbalanced hub and harmonic balancer. Have you removed those recently?

 

I had the same problem, check to make sure your sparkplugs are snug. I had to snug up my plugs cause the crush sleeves 'got misplaced' during a tune-up from a local shop, and I also had my cat cut off, one of these two things solved it for me. Didn't make it completely go away, but I can hardly tell now. I was vibing so bad I was thinking my driveshaft was unbalanced.

 

An update: I got under the car today and noticed the the #6 plug had carbon all over it. After removing the header to get it out of the way so I could tighten the plug I could clearly see that the header gasket was leaking. I'm hoping after snugging up all of the plugs and replacing the header gasket that I'll be all set.

Thanks

 

Did the plugs fix the problem becuz mine is doing the same viberation.