Collective wisdom,

I am having some engine problems with my 1991 Syncro Westy. The engine
generally is running fine, however, as I accelerate the power band
flattens out at around 3,000 rpm and acceleration or power begins to
drop off. I had recently had the van in to replace the distributor and
at that time the shop had suggested that I needed to replace the AFM.
This was several months ago and the van performed fine after I got it
back from the shop. I need some insight to what might be causing this
to happen.

Thanks,

JIm