Got a question, the pump should run a few seconds when you first turn on key? Mine runs sometimes and sometimes it don't. Seems like when temps are 10's and lower pump don't run or runs real slow. When you cycle key to off and on pump should reset and run, right? Truck has 30,000 miles. I should check pressure but too lazy. I went to get new one at dealer they won't sell any said they are on restrition. They won't sell one unless they test pump first. Can you get pump from Cummins? Thanks.