Adventures in EVAP

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2009 Jeep JK Wrangler 3.8L with a whole 12,784 miles on it. DTC's......
P0456......Small EVAP leak detected.
P0455......Large EVAP leak detected.

The shops Snap-on Solus Ultra doesn't support freeze frames on this vehicle
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I like to know what the ambient temperature & fuel level is when EVAP faults occur.

It does support a Large Leak quick test buy pulsing the purge solenoid to create a low vacuum on the Tank/EVAP plumbing.....It failed.
*This should be easy....Right?

Found a pretty large leak at the EVAP System Integrity Monitor Switch (ESIM) that's mounted to the Charcoal Canister using my Smoke Machine. Thought it was just the seal....But applying some dielectric grease to the seal didn't slow it down one bit & the seal looked pretty good.
Ordered a ESIM, Installed it....No more leak at that location via the smoke machine & re-running the quick test resulted in a pass.

My smoke machine still showed a .015" leak.....I HATE Evaporative system repair comebacks, It makes me feel amateurish. The tool is blatantly telling me there is still a leak!

The Shop Foreman/Service Writer was trying to rush me because we're months backlogged....We butt heads on a constant basis, But I held my tongue & didn't Pop-Off something smart as I've already been written-up a couple times in the last year.
I'm used to being Shop Foreman & he IS Shop Foreman, So some of the blame for the friction between us is on me! However....
I OWN my jobs, diagnostics, & workmanship.....I refuse to compromise that! Him trying to convince me it's fixed would be completely forgotten when it comes back with EVAP codes!!

I couldn't find a leak anywhere while Strictly looking for smoke, So I decided to go "Old School" & spray every connection down with Soap & Water with my smoke machine providing the pressure.

Gas Tank filler neck inlet is cracked.....Why use a different kind of plastic for the filler neck connection?

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I think you should have a notebook.... Write down the make,model, yr, date of repairs, type of repairs performed... Have your foreman sign it along with you... Helping that world champion "remember" if it is a come back... And that he signed off that in his eyes it was good enough to leave the shop. Make him take ownership.
 
Originally Posted by clinebarger
Gas Tank filler neck inlet is cracked.....Why use a different kind of plastic for the filler neck connection?


Because Chrysler.
 
evap leaks plagued my volvos. knowing the trend it was mostly easy to fix unless it was the pump/sensor unit. gas cap, solenoid, J-hose, pump/sensor unit, as my order of inspection or just parts swap (I had used spares to play with). I owned a couple of town and countries - in them it was always a fitting ... trying to remember, behind the passenger headlight? some MFRs just miss the mark on the plastic bits.
 
Good find!

Is that neck replaceable or does the whole tank need to be replaced?

Not a fan of FCA's fuel tank and EVAP system with the whole charcoal canister, etc nestled into the top of the fuel tank.
 
Originally Posted by JTK

Is that neck replaceable or does the whole tank need to be replaced?

Not a fan of FCA's fuel tank and EVAP system with the whole charcoal canister, etc nestled into the top of the fuel tank.


Whole tank needs replaced, This particular vehicle has the canister in a easy to access location.
 
Tough to tell under the soap, but it looks like you can see the crack with some staining from leaked fuel.
 
Originally Posted by Chris142
The evap system is why we can't sell our Tahoe. Nobody can fix it.



Does it have "leak" trouble codes? Surly you have some way to put low pressure in through the filler neck?

Activate the Canister Vent Solenoid using a the Bi-Directional controls via a scan tool OR Ground the White wire at the solenoid connector. In fact.....You may want to remove the Vent Solenoid & bench test it several times for leakage!! It's a common issue for them to load-up with dirt/debris & stick open.....Sometimes intermittently.

If the Vent Solenoid tests good.....Activate it, Apply 6-10 psi to the system & go over everything with a 50/50 solution of dish soap & water in a spray bottle.

Don't forget the Purge Valve line connection right behind the intake manifold, The Purge Valve connection itself. And lastly.....Purge Valve sealing integrity.
*Remove the 8mm bolt holding the Purge Solenoid, Remove the solenoid from the intake with the line still attached & spray it down.....Purge Valves rarely fail on these.

#2 in the diagram is the Canister Vent Valve.

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Originally Posted by dishdude
Tough to tell under the soap, but it looks like you can see the crack with some staining from leaked fuel.


I did see that....Funny thing is, The leak is where the filler neck adapter is adhered to the tank.
 
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