So I've been helping a friend move a bunch of tools from his shop, and one time when I went to turn the truck on, i didn't wait for the "wts" light to go off. it just cranked over for a few seconds, then I stopped and The truck was warm.

So now about everyother time I start the truck, it has to crank for about 5-10 seconds and then it'll fire up. Then the rest of the time, it fires right up like it should.....


What the heck is going on? What could it be?

Thanks for you help guys and gals!

 

The first step is to make sure you have 5-7 PSI at the outlet side of the fuel filter during the cranking period while starting. If the pressure is below that you need to diagnose the fuel system to isolate the problem.

If the pressure varies from one starting attempt to another, then look at the lift pump as having a failing bypass valve.

If the pressure is consistently low, the injection pump is likely the problem.

Given the age I would suspect either a failing lift pump or a blown diaphragm in the front injection pump housing. However, also make sure all your flexible fuel lines, including those on top of the tank, are not more than a couple years old and that your fuel filter is clean.

If the injection pump has failed, do not waste your money on just any rebuilt. Read the article on BlueChip diesel's website first.