My gas cap light came on shorty followed by the engine light. I bought a new Mopar non-locking cap, disconnected the negative battery terminal for 20 minutes, reconnected and all lights off. About 3 days/100 miles later same thing. Again with the battery terminal, again with the lights turning off, and again it is back. I've gone through a few tanks of gas and this keeps happening.

Any suggestions? I heard that this was a common problem with 3rd gen rams.

 

Im assuming this is a 2007 since you tagged it as such? Is it a CEL or a actually gas cap light on the dash because my 04 doesnt have a gas cap light.

 

I have had a cel over the years that is the gas cap. I have changed the cap when the rachet gets a little worn and the cel pop's up. I'll give the cap a couple of turns and it often cures everything. When it doesn't I put a new cap on it. I've had my truck for 6 years and I just put my forth cap on it. But to be honest this last cap wasn't really necessary but I wanted a locking cap.

 

Message indicator chimes at start up, reads "gas cap". "cel"?

A possible hole in the vaccum line that indicates leak? Or just a bad cap.....

 

my 2007 had the same issues they changed the gas tank out same thing ! then they did a pressere check of the system the cap was good so was the system 2 days later gas cap light on and check engine light on agian . back to the dealer the changed out a sencer down by the gas tank and one under the hood by the battery do not no what they were as it was all under warrenty but the truck works fine now . hope this helps

 

Big help thanks, I will suggest to them when I take the thing in.

 

My 06 did that. Turns out the seal on my evap canister was bad causing the light.

 

check all the rubber connected hoses for the evap system, if they are cracked at all replace them.

 

On my truck i have had the same thing, very recently... there should be a small canister about 2" in diameter, and about 5" long, right in front of the fuel tank, there should be 2 hoses going into each end. Check to see that this unit has not been damaged. It's very easy to sling a stone into it and bust it up! mine has about a 3/4" hole in it! This part is called the Evap system Filter, will run you about 20 bucks, i think...

 

mblatz-

Thanks for the tip. I crawled under the truck while fueling up and low and behold heard a rush of air as the fuel entered the tank-the sound was from the remaining air being forced out of a hole where a hose used to be connected before it apparently broke off. DIY fix it with a bit of crazy glue and I am back in buisness until I buy a new canister.

Thanks to all for the help!