I have already contacted Walthers, and they are not able to help me (the staff is working from home and don't have access to their warehouse to get the info I need).  

It's another week . . . post 'em if you got 'em.

I have an oval in my office where I run an N scale train. I have 27 cars and 2 identical Bachmann GP40 locos running back to back. It's been running mostly fine for a while but today the lead loco started stalling and spinning its wheels when it came to one curved section of the flat track. So I know it isn't an electrical problem. I turn the power up and it just spins faster. I cleaned the wheels of the locos and it doesn't make a difference. The track is all the same, so not sure why it's picking this particular section to have issues.

How do I turn off the momentum in a QSI Ver. 9 Titan decoder?

We operate with live loads and because we use this particular engine to switch one of the online coal tipples we need to be able to position the hopper car precisely under the coal chute. Hence the problem. 

We use a Digitrax UT1 throttle and use the toggle switch to control movement rather than constantly change speed with the knob. I have searched Google, The MRH search feature, read the QSI manual and adjusted the settings using JMRI and I haven't been able to turn off the momentum.