Plagued by Evap CEL + Loose Gas Cap Messages.

[Danneskjold184]

Hi!

So I'm plagued by Evap Check Engine Light Codes and / or Loose Gas Cap messages on the odometer. I've replaced the gas cap twice in the ~12 months since I bought the truck with caps from Advance Auto. I've also replaced the Evap System Leak Detection Pump and the Vapor Canister Purge valve.

I've also had an intermittent problem with fueling up. The gas would quickly kick back up the filler tube and kick the fuel pump sensor shutoff. Sometimes this problem would go away. Sometimes it would come back. It seems to be worse than ever. I just spent 5 minutes trying to get 6 gallons in the truck.

At one point I took off the fuel filler line and the vent tube and blew air / tried to clean out the steel upper part, to little effect.

Is it something on the gas tank? Is it clogged? I'm seeing various answers like I need to replace the Charcoal Canister. Or it's a stuck rollover valve on the Fuel Tank itself. Or is it the upper fuel filler neck attached to the side that needs to be replaced?

Thanks for the help.

 

[RodeoRam]

Have you had the fuel system smoke tested? If the gas cap is not the problem, a smoke test should show where the leak is before you go throwing parts at it. Might have saved you some money.

Use this site's search function for the gas tank fill problem. There are plenty of threads about it.

 

[Danneskjold184]

Have you had the fuel system smoke tested? If the gas cap is not the problem, a smoke test should show where the leak is before you go throwing parts at it. Might have saved you some money.

Use this site's search function for the gas tank fill problem. There are plenty of threads about it.

When I got it inspected, they did a smoke test and immediately discovered that all the lines had been replaced, and not been properly tightened.

They reset the CEL, and I took the truck home to fix the other issues (I did all the front ball joints, brakes, rotors, one brake caliper, and rear bumper). Brought it back for reinspection and the CEL came back, same issue. General Evap System failure and Loose Gas Cap. Even after getting a brand new gas cap.

I can get it smoke tested again, but I feel like it's a wild goose chase and was wondering if there was anything obvious I was missing. Before just tossing more money at a mechanic rather than doing it myself.

 

[kevkev]

A cheap fix is clean the fuel cap o ring and neck with alcohol. If you still get that , do you put gas ion your truck with it running? that used to give me codes all the time.

 

[GTyankee]

Dodge Rams do not play well with after market gas caps, at least on the 4th Gen trucks.
I never researched 3rd Gen trucks

By the way, check to see if the PURGE Valve was installed right side up.
I think there was an arrow imprinted on it


video about your truck

Dodge Ram Purge Valve Solenoid p0456 p0440 p0441 p0453

This video shows how to test a Purge Solenoid Valve on a 2003 Ram 1500 and confirm if it is functioning properly and sealing during EVAP emission system test...

www.youtube.com

 

[bgenlvtex]

Fuel tank pressure sensor

 

[aszumilo]

None of my Rams liked aftermarket gas caps (1996, 2004, 2011). Last aftermarket one I had would throw the CEL when it got about 1/2 tank. Replaced it with an OEM cap, from the dealer, and haven't had a light since.

 

[PA Ram]

None of my Rams liked aftermarket gas caps (1996, 2004, 2011). Last aftermarket one I had would throw the CEL when it got about 1/2 tank. Replaced it with an OEM cap, from the dealer, and haven't had a light since.

I used, Gas Cap,Fuel Cap For 2000-2019... https://www.amazon.com/dp/B08CR8YZC3?ref=ppx_pop_mob_ap_share

I was throwing the generic gas cap code and the cap didn't fix it. I checked my ESIM and mine was shot. Replaced it and cleared code months ago. No codes since even with the aftermarket cap and ESIM. I have a 2017 Ram 1500 5.7