When it stopped, could you hear the pump squealing? When it starts, does it start readily or is it hard to restart? In addition to checking the fuel pump, This could also be a lower injector washer leak, compression gasses leak past the sealing washer into the fuel gallery and aerate the fuel when loading the engine.
Engine will slowly drop cylinders  and lose power until it stops, then a rebleed will be required to start it again. Once started it'll run for a while until another hill or higher engine loads like highway speeds, and then start it all over again.
JC
				
			 
			
		 
			
				
			
			
				The Isuzu 110. Solid and as dependable as a rock, coming soon with auto box😊
The Range Rover L322 4.4.TTDV8 ....probably won't bother with the remap..😈
			
			
		 
	
Bookmarks