Just bought this 2003, ram quad, 4x4, 1500, hemi, after four days driving the engine light goes on and it ended up to be a evap 0440 code. I took the advice here did the gas cap thing...no luck, then looked at the hoses sure enough the 5/8" i.d. hose to the evac can was split and one was missing a clamp. I had the code reset put on a new gas cap, drove for two days and the light came back on! Checked the code and....it said no code found so is this just a trouble fault that will clear on good system checks?

 

The code should show up if the light is on. Might try a different code reader.

 

Sure enough the P0440 code came back, I'll take it in for a smoke check. Things look good as far as I can see and hoses seem firm with no damage.

 

Yep, I'd say if'n that hose was split, there'd be another one in the evap system someplace...

 

Dropped the truck off at the dealer, they ran a check and it came back as the rear oxy senser. Said you need to enter to correctly read codes via Chrysler path not the generic path.......no charge to read the code so I had them crank the torsions and do an alignment, really like that leveled out look.

 

Your p0440 came back as a o2 sensor!? That's so odd!! I didn't know that has to do with evap emission system? Usually the scanners will say o2 sensor bank 1 downstream or something like that

 

Bob,
I had the same error code on an 03 hemi. Replaced gas cap, error came back. Got under there and found hose clamps were missing on the 5/8" hoses, fixed that and cleared the codes. They came back again. Then I spread some petroleum jelly around the rubber seal of the gas cap and has not thrown a code since.

Good luck