If you have a vacuum pump available, try pumping down the pressure in the WUR as it starts to warm up. If you pull it down to about 15-16"Hg. below atmospheric, the control pressure should stay below 2.5 bar. If, however, the WUR will not hold vacuum, you will have found at least one part of the problem. At cold start the control pressure might be below 1.0 bar; if so, try leaning the idle mixture slightly in 1/8th turn increments (CCW).

Hi there -- I have a new issue --

I've installed a new WUR but now what happens is I'm getting a flutter in the measuring plate.

It extreme at times -- and the engine is running very poorly still.

What could be causing this? Faulty damper??