[NYCDahon]

Hi

I tried cleaning the gas cap and top of filler tube but after a few days I got the yellow engine light and the return of the P0456 code. Should I jump to a new gas cap? My cap still looks newish - nit sure when it was changed - it had 90,000 miles when I got it and I now have about 135,000 miles on it.
(3.4L - 2004 Concorde Limited)

I have a 2003 Jeep Grand Cherokee - it happens to have the same gas cap - maybe I should switch them and see if the yellow engine light follows the Concorde cap.

Are these tethers easy to move?

Cheers

 

[peva]

Do a search on 'P0456' without date restriction - sorted by date (in general, later threads reflect info. that matured over the years).

In doing a quick search and some skim-reading, I saw mention of a pump built into the evap. system plumbing (on top of the gas tank), and the purge solenoid (located next to the brake booster on the '04). Be aware that the evap. system went thru major design changes over the years (especially prior to '02) - so pay more attention to discussions specific to '02 thru '04 model years.

 

[NYCDahon]

Do a search on 'P0456' without date restriction - sorted by date (in general, later threads reflect info. that matured over the years).

In doing a quick search and some skim-reading, I saw mention of a pump built into the evap. system plumbing (on top of the gas tank), and the purge solenoid (located next to the brake booster on the '04). Be aware that the evap. system went thru major design changes over the years (especially prior to '02) - so pay more attention to discussions specific to '02 thru '04 model years.

Thanks Peva!

I will do that as soon as I wait for the outcome of my lazy man's test. I just switched the caps of my '03 Jeep WJ with my '04 Concorde.

Any bets out there? Will the P0456 code follow the cap or not?

Looking at both caps objectively - they both could really use new replacements - also in the city they both should really be the tethered type - but sadly tethered caps are surprisingly hard to find - at least from any company that I have ever heard of. On the other hand, cheep generic ones with tether cords are everywhere....

BTW - Here are my caps - and yes my jeep cap was untethered! Haha

 

[NYCDahon]

So far - so good! No light today - will give it a week before I pronounce it solved!

 

[NYCDahon]

4 days and still no CEL. 🤞

 

[Alexey]

The tank cap rarely fails, I recommend looking at the plastic tubes that go to the EVAP valve under the hood, they often melt or break. And sealing rubber bands, they can be said to be eternal.

 

[NYCDahon]

It seems to have been a bad cap - it has been a week and I drove. 300 miles today - no return of light! Thanks for all the help.

 

[Ronbo]

Buy a new cap from the Dealer and be done with it !

 

[NYCDahon]

I did just that - I got a deal on this - it is the same cap - just with a shorter tether - but the tether easily swaps with the old longer one.

 

[NYCDahon]

All solved - no more CEL! It was just the gas cap.

 

[peva]

Woohoo!

 

[Scooter-Man]

I lived with that code for YEARS - and replaced gas cap. Purge cansiter or lines in my car went bad. Didn't want to drop the gas tank to find the problem.

 

[NYCDahon]

I just replaced all that stuff including the gas tank on my 2003 Jeep Grand Cherokee. It wasn't cheap - nor easy - but I guess I got lucky here and it is just the gas cap.

 

[NYCDahon]

Haha - no luck. I got the code again today. I just recleaned the fill inlet and tightened the cap. I then cleared the code - but I must assume I will soon be checking first little hoses then bigger ones...

 

[Ronbo]

Hoser !

 

[NYCDahon]

Hey Hoser

Besides hoses any advice - I read that you can easily test the Evap Canister Purge Solenoid's Suckage while car is running. Suckage is bad.
Apparently, according to what you wrote in these forums a few years back -this Solenoid is located right by the airbox - however Peva said 6 years ago that it might be located behind the engine on 2002 and later models...

I have a 2004 Concorde Limited 3.5L - either of you gents know where mine is?

I will check the old electrical connector too - once I find the damn thing.

 

[Ronbo]

On 2002+ 3.5L cars. Evap Purge Solenoid should be on the firewall near the brake booster.

 

[peva]

On 2002+ 3.5L cars. Evap Purge Solenoid should be on the firewall near the brake booster.

Yes - per post no. 2.

 

[NYCDahon]

I will look at that first thing in the morning.

Thanks to both of you!

Cheers

 

[NYCDahon]

Darn code has returned. Haha