I have been having an ongoing problem with my 2001 Sierra 3500 With Duramax 6600 Diesel. When I run the truck for an hour or so and turn it off, it will not re-start unless it sits for 30-40 minutes. The engine will crank, but never fire. I can try and try unti lthe battery runs down, but the truck refuses to fire.


I have replaced the fuel filter and the fuel pressure regulator, but the problem continues. Someone told me that there is a second fuel filter next to the gas tank and I should replace it. I checked under the truck and there looks like another filter is there but it looks like a square air filter of some sort. I can't find anything online about it to replace it or to even verify that it is a second fuel filter. Does anyone know about it? Also if anyone has other suggestions, please feel free to volunteer them. I am runnung out of ideas and I love my truck too much to get rid of it.

Do you have the juice?


Have you paid attention to see if their is a security light flashing on the dash when this happens?


There is no 2nd fuel filter unless it was added in after.

... I checked under the truck and there looks like another filter is there but it looks like a square air filter of some sort..


Sounds like you are describing the fuel cooler. (see pic) (http://community.webshots.com/photo/67970835/72256955gitKgX) As Max power said, a stock DMAX has only one fuel filter mounted on the drivers side of the engine. When your truck won't start try pumping the primer (on top of the fuel filter assy) until hard. If the truck starts after pumping the primer you most likely have a loss of prime.


http://www.dieselplace.com/forum/smileys/Geek.gif


Edited by: jbplock

The square looking filter thing that's in front of the fuel tank is the return fuel cooler. Try repriming your filter, might have air in it. Look under the do it yourself articles. Basically unsrew the bleed screw on top of the filter and pump the primer till fuel comes out, then tighten the screw and pump a few more times, then see if it starts. Also, make sure the water drain on the bottom of the filter is snug. Hope your problem is that simple, good place to start anyway. Good luck.

I had the same problem after my fuel filter was changed. I noticed at first my truck was running rough. The next day it started fine, went to work and when I tried to start it to go home it wouldn't crank over. My first tought was the fuel filter because it was starving for fuel. I primed the filter & she stared up, next day same problem. They screwed the O ring wnen putting on the filter & I had an air leak in the fuel system. Hope it that simple for you.

Remember that the Duramax does not use a lift pump in or near the tank. The fuel lines WILL NOT LEAK FUEL if they get a break. You will keep losing prime because air will get into the lines at the break. Inspect your lines from the filter to the tank REAL good.


Ed