P0456 small evap leak. Replaced gas cap and LDP, smoke test no leak. What's next? - Jeep Garage - Jeep Forum

Go Back   Jeep Garage - Jeep Forum > Jeep Platform Discussion > Grand Cherokee - WJ

Join Jeep Garage Today
Reply
 
Thread Tools Display Modes
 
  #1  
Old 12-17-2014, 03:24 PM
JTS97Z28's Avatar
Premium Member
My Jeep: 2015 3.6L WK2
 
Join Date: Jan 2011
Location: Plainfield, IL
Posts: 3,861
Thanks: 88
Thanked 618 Times in 455 Posts
Rep Power: 28704
JTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond repute
P0456 small evap leak. Replaced gas cap and LDP, smoke test no leak. What's next?

2004 Overland 104,000 miles. Started getting the somewhat common P0456 small evap leak detected code. Obviously there is a lot of info to be found in a search, but at this point I'm unsure what to do next.
I started with the easy thing and replaced gas cap with new OEM part. Code came back within a few days. I inspected hoses and from what I could see they looked fine. I then had a shop do a smoke test and diagnose. They said no leak found, but tested the Leak Detection Pump (LDP), and said it tested bad. I bought a new OEM part and installed. Problem seemed fixed as the light stayed off for longer than normal. As luck would have it the light came back today with the same code. Only difference is the outside temps went down a little lower than its been, but besides that nothing had changed. I will be taking it back to the shop that told me the LDP was bad which apparently it wasnt. Assuming I won't get anywhere with them, can anyone point me in the right direction for what to do next?

Thanks.

__________________
2015 Jeep Grand Cherokee High Altitude, Bright White, V6, HK audio
Reply With Quote
Sponsored Links
Advertisement
 
  #2  
Old 12-18-2014, 06:10 PM
Frango100's Avatar
The beast from Brazil

My Jeep: 2004 4.7L WJ
 
Join Date: Dec 2009
Location: Brazil
Posts: 7,324
Thanks: 17
Thanked 377 Times in 364 Posts
Rep Power: 529483
Frango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond repute
Re: P0456 small evap leak. Replaced gas cap and LDP, smoke test no leak. What's next?

Did you have a good look at the hoses which run around the rear axle, because they tend to dry out and cause leaks. You also checked the line in the engine bay, going to the EVAP solenoid? The EVAP solenoid could have an internal leak, so plug the line to the solenoid and check again.
__________________
Frank

JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
KYB Gas-a-Just shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.

VW Beetle 2.0 TSI 2013
My new toy
Reply With Quote
  #3  
Old 12-18-2014, 06:28 PM
JTS97Z28's Avatar
Premium Member
My Jeep: 2015 3.6L WK2
 
Join Date: Jan 2011
Location: Plainfield, IL
Posts: 3,861
Thanks: 88
Thanked 618 Times in 455 Posts
Rep Power: 28704
JTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond repute
Re: P0456 small evap leak. Replaced gas cap and LDP, smoke test no leak. What's next?

Quote:
Originally Posted by Frango100 View Post
Did you have a good look at the hoses which run around the rear axle, because they tend to dry out and cause leaks. You also checked the line in the engine bay, going to the EVAP solenoid? The EVAP solenoid could have an internal leak, so plug the line to the solenoid and check again.
Im off work for a week so I plan on double checking everything. I'm even gonna remove the rear bumper to access everything easier behind the rear wheel. But like I said I had a shop do a smoke test and they said its a sealed system with no leaks.
__________________
2015 Jeep Grand Cherokee High Altitude, Bright White, V6, HK audio
Reply With Quote
  #4  
Old 12-18-2014, 06:31 PM
Frango100's Avatar
The beast from Brazil

My Jeep: 2004 4.7L WJ
 
Join Date: Dec 2009
Location: Brazil
Posts: 7,324
Thanks: 17
Thanked 377 Times in 364 Posts
Rep Power: 529483
Frango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond repute
Re: P0456 small evap leak. Replaced gas cap and LDP, smoke test no leak. What's next?

But a smoke test will not reveil an internally leaking evap purge solenoid valve.
__________________
Frank

JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
KYB Gas-a-Just shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.

VW Beetle 2.0 TSI 2013
My new toy
Reply With Quote
  #5  
Old 12-18-2014, 07:19 PM
JTS97Z28's Avatar
Premium Member
My Jeep: 2015 3.6L WK2
 
Join Date: Jan 2011
Location: Plainfield, IL
Posts: 3,861
Thanks: 88
Thanked 618 Times in 455 Posts
Rep Power: 28704
JTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond repute
Re: P0456 small evap leak. Replaced gas cap and LDP, smoke test no leak. What's next?

Ok I will check that. What exactly do you mean by plugging the line?
__________________
2015 Jeep Grand Cherokee High Altitude, Bright White, V6, HK audio
Reply With Quote
  #6  
Old 12-18-2014, 09:54 PM
Frango100's Avatar
The beast from Brazil

My Jeep: 2004 4.7L WJ
 
Join Date: Dec 2009
Location: Brazil
Posts: 7,324
Thanks: 17
Thanked 377 Times in 364 Posts
Rep Power: 529483
Frango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond repute
Re: P0456 small evap leak. Replaced gas cap and LDP, smoke test no leak. What's next?

You just have to disconnect the line from the EVAP purge solenoid valve and plug (close) the line with something suitable. If the fault code doesn´t come back, then the purge solenoid valve is most probably internally leaking. You will have to plug the line which goes to the EVAP system and not the one which goes into the engine air inlet.
__________________
Frank

JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
KYB Gas-a-Just shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.

VW Beetle 2.0 TSI 2013
My new toy
Reply With Quote
  #7  
Old 12-19-2014, 10:57 AM
JTS97Z28's Avatar
Premium Member
My Jeep: 2015 3.6L WK2
 
Join Date: Jan 2011
Location: Plainfield, IL
Posts: 3,861
Thanks: 88
Thanked 618 Times in 455 Posts
Rep Power: 28704
JTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond repute
Re: P0456 small evap leak. Replaced gas cap and LDP, smoke test no leak. What's next?

Quote:
Originally Posted by Frango100 View Post
You just have to disconnect the line from the EVAP purge solenoid valve and plug (close) the line with something suitable. If the fault code doesn´t come back, then the purge solenoid valve is most probably internally leaking. You will have to plug the line which goes to the EVAP system and not the one which goes into the engine air inlet.
Ok I'll go do that now. So just to verify I will leave the wire harness attached and do nothing more than yank the line that connects to the purge solenoid under the hood and goes to the evap system at the back of the car and simply plug that line.
So am I basically isolating that solenoid to eliminate it as a possible leak point? The CEL is currently on, should I leave it on and see if the light goes off by itself? That may happen sooner rather than resetting the light and waiting for it to come back on.

---------- Post added at 09:57 AM ---------- Previous post was at 09:32 AM ----------

Here is a picture of what I did and let me know if this is correct. I blocked the line that goes from the purge solenoid to the evap system in the back (circled in red). It was easier to just block it at this connection rather than at the actual solenoid. I used a couple layers of cling wrap and put the rubber connector back on which should be essentially sealing off that line.

__________________
2015 Jeep Grand Cherokee High Altitude, Bright White, V6, HK audio
Reply With Quote
  #8  
Old 12-19-2014, 11:50 AM
Frango100's Avatar
The beast from Brazil

My Jeep: 2004 4.7L WJ
 
Join Date: Dec 2009
Location: Brazil
Posts: 7,324
Thanks: 17
Thanked 377 Times in 364 Posts
Rep Power: 529483
Frango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond repute
Re: P0456 small evap leak. Replaced gas cap and LDP, smoke test no leak. What's next?

Yes, that should work.
__________________
Frank

JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
KYB Gas-a-Just shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.

VW Beetle 2.0 TSI 2013
My new toy
Reply With Quote
  #9  
Old 12-19-2014, 04:05 PM
JTS97Z28's Avatar
Premium Member
My Jeep: 2015 3.6L WK2
 
Join Date: Jan 2011
Location: Plainfield, IL
Posts: 3,861
Thanks: 88
Thanked 618 Times in 455 Posts
Rep Power: 28704
JTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond reputeJTS97Z28 has a reputation beyond repute
Re: P0456 small evap leak. Replaced gas cap and LDP, smoke test no leak. What's next?

I just spoke with the shop that did the smoke test and they said that besides not seeing any smoke, but they also watch to see if it loses any pressure which it did not. So I would imagine that would eliminate any internal leak at the purge solenoid as well?
__________________
2015 Jeep Grand Cherokee High Altitude, Bright White, V6, HK audio
Reply With Quote
  #10  
Old 12-19-2014, 07:39 PM
Frango100's Avatar
The beast from Brazil

My Jeep: 2004 4.7L WJ
 
Join Date: Dec 2009
Location: Brazil
Posts: 7,324
Thanks: 17
Thanked 377 Times in 364 Posts
Rep Power: 529483
Frango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond reputeFrango100 has a reputation beyond repute
Re: P0456 small evap leak. Replaced gas cap and LDP, smoke test no leak. What's next?

Yes, if they had no pressure loss, then the EVAP purge solenoid should be ok. Then it can almost only be wiring.
__________________
Frank

JEEP Grand Cherokee 4.7 Lmtd 2004
HID 8000K in low and fog / Quad Squad member
KYB Gas-a-Just shocks / Pirelli Scorpion ATR 245/65/17 - Transgo reprogramming shiftkit.

VW Beetle 2.0 TSI 2013
My new toy
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
"Evap System Small Leak" - P0456 2014_SRT_Steel Trouble Shooting/Problems/Service 26 11-27-2016 02:41 PM
evap leak pensfan414 Trouble Shooting/Problems/Service 7 02-01-2014 12:03 PM
Cylinder 1 Missfire, Evap Leak. Hellcat89 Troubleshooting/Problems 5 05-10-2013 07:28 AM
P1495 LDP Solenoid Circuit Martyp Troubleshooting/Problems 0 06-04-2012 03:43 PM
p1494 LDP replacement violant00 Troubleshooting/Problems 4 03-03-2011 11:39 AM

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 09:52 PM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Copyright 2012 - JeepGarage.Org
The Jeep Grand Cherokee Owners Community

JeepGarage.org is in no way associated with or endorsed by FCA US LLC. Chrysler, Dodge, Jeep, Ram, Mopar and SRT are registered trademarks of FCA US LLC.