Vibration during accel

[JTodd]

I have a fairly noticeable vibration when accelerating slowly. It seems to shake everything in the front and tends to happen at lower RPMs and fades away around 2000. If I lift off of the throttle the vibrations instantly stops. The truck starts and idles just fine and without any noticeable vibrations. I checked the drive shaft as the U-joints where the first thing I thought of. The next thing I can think of is the harmonic balancer. How is that checked out? After that, what are some suggestions?

[rustyk]

The damper can be visually checked. Mine was so shot the stops were clicking...

In my Ford (can I say "Ford" on this forum?) van I had a similar issue which was belt separation on a rear tire.

But don't discount a dirty injector.