so i posted many times about my cold start issue, and then about my troubles finding a shop, and about how I finally ended up at the dealer to diagnose and eventually fix the rig. Apparently it was the pressure relief valve on my fuel rail.

of course, when I went to get the truck this morning, the mechanics were all hiding so I couldn't ask them questions about their discovery, so I will ask you all.


why would a leaking pressure relief valve only be an issue when the truck is unplugged, and make itself apparent only when it is cold? maybe its just me, but that didnt make sense.

 

It takes more fuel to get a cold engine started than a warm or room temperature engine started. The pressure relief valve was letting more fuel by-pass and not letting the rail build enough pressure to push enough correct atomized fuel into the cylinders to fire off a cold engine.

 

that makes sense. thanks for that man.