Hey

I've got an 86 b2000 that was run questionably by the previous owner. It's run solid for about 6 months now, but lately it's started to stall when I let the revs below 1500 and hit the brake at the same time (usually in 1st, slowing at intersections in heavy traffic). The revs fall, and it feels like the clutch is engaged even when I put the pedal to the floor (I can't move the gearshift). When I tap the gas, it goes away until the next time I hit the brake. I can also lower the revs at idle from 1000 to about 500 by pumping the brake in neutral.

Anyone ever have this happen/have any ideas?
Thanks!

Devin