Have an '02 HO/nv5600. Drove through single digit temps with no trouble, Used 1/3 bottle of Howe's Engine Treatment anti gel to 35 gal of fuel, made a crude winterfront out of cardboard. Engine temp gauge did not drop, heater kept me comfortable. Did notice a little different noise in the engine, fuel pressure gauge stayed at 14psi. Next morning cycled the grid heater twice and she cranked right up, FP 20. Let it warm up 15min outside temp-4f. Drove less than a mile and she started missing like crazy, fp dropped to zero, turned around and idled back to motel, shut her off and cycled the switch 3 times and got PO216 and PO121. Pretty sure the fuel gelled up and plugged up the filter. My question is does the PO216 mean the vp44 is really fried and I need to find another way to make the 600 mile trip home, or will adding more Howe's, and changing the filters fix the problem well enough to make the 600 mile trip home without needing a wrecker at some point in time.?