04 WJ 4.7 HO

Is removing the bumper the only way to get to and replace those hoses? I got a P0455 code and pending P0442. Found a split hose that was off its connection on top of the EVAP canister and goes somewhere towards the fuel tank.

 

Can't tell you about the 4.7. My evap canister on the 4.0 is right next to the brake booster.

 

Yeah unfortunately this one is back behind the drivers reae wheel.

 

That sounds like an engineer's wet dream! "Now where do I have room for this? I think I'll put it right where it can get damaged by flying stones!"

 

It's protected by the inner wheel well and it's tucked up inside behind the side of the bumper. But yes, not the most ideal spot ever.

 

Then the answer to your original question is yes, you'll probably have to remove the bumper. Can you unmount it and drop it down to get to the hoses?

 

I'm gonna try and get in behind the inner wheel well and see about unmounting as well. To be honest, I haven't really gotten under there for too long to see how to go about doing it.

 

Can you keep us posted because i have a 2004 4.7 that has code P0455 and it wont pass inspection...in fact the inspection expired in December and i haven't had a chance to pull the bumper yet...its my second vehicle so I've been using my DD...if you get to it before me i would be happy to hear how it went and vice versa..thanks

 

I found two bad hoses(technically one hose that uses a splitter to connect the 2) on top of the rear canister behind the driver's rear wheel. They were spilt and rotting at the connection points. You can gain access but you have to remove a small inner fender piece and a bracket holding some other hoses. The hose that was bad was on top of the canister and connected to another hose using a splitter. When I replaced the hose I did away with the splitter and just used one piece of hose. So from the top of the canister it connected to a t-junction in front of the gas tank but it was easily accessible. It's tight on top of the canister but can be done without removing the bumper but would certainly give you more room if you removed it.

I cleared the codes but have not check the readiness monitors yet. 60 miles and the cel has stayed off. I will check the monitors when I get home from work to see if it will pass inspection. If you have a p0455 code my guess is that is most likely where it's coming from.

 

The way this system works is on cold startup, the leak detection pump pulls a vacuum on the evap system. If it holds, it shifts over to the purge solenoid that continually cycles to suck any vapors that have accumulated in the canister. Vacuum is the hardest to seal so if the test doesn't hold, it sets a code and the purge solenoid doesn't cycle. Even the tiniest crack in a hose will fail the vacuum test. This is where the fuel cap gets involved. Loose or leaking cap, no vacuum. The vacuum level is very slight to allow the fuel pump to draw fuel while the test is performed. Then the tank goes to atmospheric, vented thru the canister.

 

Thanks Dave. I had a pending p0442 (small leak) DTC. The current gas cap looked a little wonky so i replaced it with a Mopar one just to be sure.

 

Not sure this will help but I just happen to have my bumper off and lights out so I popped a few pics. Looks like if you take the lights out you can inspect and disconnect the hoses from inside the light buckets. It also gives you access to the 3 nuts that hold the can if you need to drop it down. I'm assuming that's the can your talking about. Hope this and pics help...

 

I changed my gas cap for a mopar one back in the fall to get rid of theP0442 code now i have the P0455...when i get some free time I'll try what you said...thanks..ill keep you informed on my progress

 

Hey JimmyBo, that ground connection looks like it's getting really wonky. You might want to clean it up before you put the bumper back on.