I had an interesting situation this morning...I fired up the truck this morning as normal, grid heaters kicked on and I waited for them to go out and proceeded with normal start-up. Got out and moved my garbage cans as today was garbage day. While moving the cans, after about 30-45sec of run time I hear a loud bang. Now for me being a gasser guy for a while I would percive this to be a backfire. I understand that diesels can't backfire due to no plugs. What could have this been? My a/c was off and defroster was off as well....Also, after this noise I got a strong smell of diesel....This was 5am so i could not see if there was any smoke associated with this event. I am wondering if a diesel could backfire through the intake and ignite unburned fuel with the grid heaters? I have checked my oil level and all is good.(thought I might have cracked an injector)

Then this afternoon after work same thing happened with the same senarios, except it happened within 5-10sec of run time.

Has anybody heard of this happening and causing problems???
Quad was on level 0 and SMARTY is not in.....No DTC or anything just leaving me wondering??????

 

How loud like a shotgun blast? Usually a backfire is from lack of fuel. One time I had a filter get dirty after driving about 3,000 miles on it. I was getting up to speed and pow loud as blast out the tail pipe changed the filter and fine. I would start there.

 

Mine does the same thing every once and a while. I also would like to know what it is.