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Getting CEL Evap Leak

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Old May 17, 2010 | 07:06 AM
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Default Getting CEL Evap Leak

I am getting a CEL every few days now. EVAP gross leak mostly ,once in a while EVAP minor leak. Just before I started to get the CELs I got a "Tighten Gas Cap" message. The cap was feeling loose and worn so I replaced it with a new Stant brand cap but I am still getting CEL. Any ideas?
Does anyone know know if this would fall under warranty? Isn't the pollution control devices on our cars warrantied longer then basic warranty? I thought 75-80,000 miles. I have over 64,000 on my 07 Monte SS
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Old May 17, 2010 | 08:01 AM
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Emissions warranty is something like 8/80,000. Sounds like your evap system needs to be hooked up to a smoke machine.
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Old May 17, 2010 | 12:04 PM
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No, this will not be covered by the emissions warranty. The Cat Converter is about the only thing that is...even O2 sensors are not covered.

My suggestion? Replace the EVAP vent solenoid back near the fuel filler neck. It's a ~$30 part from the dealer and takes 5-10min for even the most dimwitted car guys ;-) Chances are likely you'll find that the code you're throwing is a P0455 or in that range. That solenoid is usually the first of the 3 major EVAP components to go, and it typically starts with the "Tighten Fuel Cap" message.

If you lay under your driver-side rear bumper and look up towards the filler neck, you'll see a small black cylinder with a rubber hose and wiring harness connected to it. That's the culprit 95% of the time. The only issue I see with this repair is that the bracket it mounts to can get pretty rusty and not allow easy removal. Aside from that, there's a spring clamp holding the vapor hose in place, and a single wiring harness that needs to be detached.

Check out this thread for more info/owner experiences.
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Old May 17, 2010 | 09:53 PM
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Thanks alot for the info, I'll check that out
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Old May 29, 2010 | 05:29 AM
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Well went to the dealers (stealers) and bought a new evap vent solenoid assembly. You gotta buy the whole assembly, inc. bracket, solenoid, canister and plastic hose. $90 with tax. Easy replacement, just a pia to get your hands in the tight quarters, plenty of other hoses and muffler in the way of the plastic hose to the tank. Only one bolt holds the bracket and plastic hose slips into a rubber hose.... easy.
Maybe it's me, but seem to run better, more power after repacing.
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Old May 29, 2010 | 10:19 AM
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If the purge solenoid was opening and the vent solenoid was not, you're gas tank would end up under a vacuum every time the evap system tried to work. That will make the engine run really rough by jerking the fuel pump around.
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Old May 29, 2010 | 03:13 PM
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I am thinking the vent solenoid was opening too much or stuck open as I was getting both "tighten Gas Cap" message and CEL: gross evap system leak.
Anyway. its done, we'll see if I get anymore codes
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Old May 29, 2010 | 09:55 PM
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Wow they made you get all the hose work?Must be something new now. I got just the soleniod/filter for $30. Fixed it though.

Rock Auto sell this part also.
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