2002 stock cummins hard starting

[Cummins_HO]

My friend has a 02 2500 cummins, all stock, other then a fass 150 system on it. if he parks the truck with the back end higher then the front it starts just fine. But if the front is higher then the back, it will hardly start...im baffled! thank you!

 

[CSnyder]

crossover tube o-rings bad

 

[Cummins_HO]

Ok thank you! Ill let him know and try that.