i have and 03 lightning and when i gas on it i blow the hoses to the dpfe sensor off why is there presure blowing them off when they should be making a vacuum?

 

The cats may be plugging up or there's another restriction in the exhaust system.

 

Mufflers often rust internally and restrict the gas flow, especially if OEM. If original equipment, I wouldn't over thinkit, simply sawzall muffler/catz at a time off.

 

Me too...03 Lightning i replaced the DPFE sensor and since then, they've been blowing off constantly..mostly just one (newer tube is parallel,stock ones went north & south) so the one i'll call it left if your standing at the front of the truck,just sorta slides off every day..super annoying looking for a new hose right now to help out possibly. Exhaust is only 2years old so should still be in good condition..?