Tim,

"Can possibly a very stiff throttle cause the actuator to pull enough current to fry these things?"

YES!!!

You can actually measure current draw to the actuator. Normal current draw will be between 120-180mA @ 13.8VDC.

Test the actuator spinning in both directions when measuring.
Operation should be smooth, not loud, not rattle, nor have current spikes while running.

__________________
Chris
1985 300SD - 'Grace' (198K mi.)
2018 Honda Civic Sport
2018 Honda CRV LX
2010 Honda Fit Sport (RIP)
2013 Honda Accord Sport (Sold)
1996 Lexus LS400 (Retired)
1995 Ford Contour SE (Retired)
1976 Porsche 914 (Sold)
1972 Datsun 240Z (RIP)