I have a 2004 Schwing 47 mounted on a mack. Randomly while pumping the machine will throttle all the way down. I can immediately throttle it right back up and keep going. Some days it won't do this at all. Then it might just do it once. Other times it might do it 4 times in a row. I've checked the wiring in the dog house. I've checked the wires in the remote box. Any ideas?

Totally a shot in the dark...but, is your jake brake switch on clutch giving you any problems?  I think if that gets tripped, you will lose your RPMs but as soon as it is in normal position you can rev right back up.  Ive never had that problem unless some other operator was playing a joke!  Only other throttle issue I have had was on a Putz that the cruise control switch had to be ON but not set in order to rev up with remote.  Call Cole and Lambert in Ashland VA.  They are pretty good on diagnostics.

Thank you 

Have had same problem with Concord. Mine is a truck issue. There is a faulty sensor on back of parking brake which sends a signal that air is low therefore turns rpm down to truck idle. Worse in winter when heat is cranked. On one of my pumps just cleaned spade terminals and never did again. If you lose rpm and cant get back try tapping on parking brake on doghouse usually comes back. 

check/ replace the two air brake switches right underneath the cab on the driver side,