4.2L: "Evap Emissions Incorrect Flow," "large leak," "Catalyst below threshold"...
06-27-2009, 05:34 PM
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4.2L: "Evap Emissions Incorrect Flow," "large leak," "Catalyst below threshold"...
Does anyone have experience with these codes? I've got the 4.2L.
I couldn't spot anything obviously wrong under the engine covers. The hoses I could reach seemed fine.
16825 - Evap Emission Control Sys: Incorrect Flow
35-10 -- Intermittent
16814 - Catalyst System Efficiency below threshold (Bank 2)
35-1- -- Intermittent
16839 - Evap Emission Control Sys: large leak
35-00 --
I reset with VAG-com but the check engine light is back on.
Suggestions from similar messages:
All the engine codes are related, and indicate a bad hose somewhere.
A hose connecting the EVAP purge system to the intake manifold is either disconnected or cracked/split. The EVAP purge system collects/stores/meters fuel vapors from the tank, and then directs the vapors into the intake manifold to be burned.
The trans code indicates the brake light switch is faulty. You can clear that code, and see if it reoccurs. If it does, replace the switch.
==
your purge valve is stuck open causing both faults, above the air filter housing there is only 1 solenoid valve there. canister is back of car under the trunk. remove the 3 13mm nuts and drop plastic cover, you'll see it. when you replace those parts blow the line for the purge valve. the carbon broke up causing purge issue & carbon is most likly causing purge valve to fail. you can pinch off before purge valve and run test to verfy 1 fault goes away.
==
My bet is that your charcoal cannister for the fuel overflow is bad also and is ..
causing your purge valve to fail and throw a code. Clear the CEL via VAG after changing the purge valve but if the same codes come back next time I would change the charcoal cannister.
Actually I was told that it gets filled up from the over flow when you top off the tank<more>
When they changed my charcoal cannister at 80k miles he said the difference in weight between the new and old was incredible because of the all the gas that got absorbed into the charcoal. Got rid of my EVAP codes once and for all. Topping off your tank is a big no no in my book after that.
I couldn't spot anything obviously wrong under the engine covers. The hoses I could reach seemed fine.
16825 - Evap Emission Control Sys: Incorrect Flow
35-10 -- Intermittent
16814 - Catalyst System Efficiency below threshold (Bank 2)
35-1- -- Intermittent
16839 - Evap Emission Control Sys: large leak
35-00 --
I reset with VAG-com but the check engine light is back on.
Suggestions from similar messages:
All the engine codes are related, and indicate a bad hose somewhere.
A hose connecting the EVAP purge system to the intake manifold is either disconnected or cracked/split. The EVAP purge system collects/stores/meters fuel vapors from the tank, and then directs the vapors into the intake manifold to be burned.
The trans code indicates the brake light switch is faulty. You can clear that code, and see if it reoccurs. If it does, replace the switch.
==
your purge valve is stuck open causing both faults, above the air filter housing there is only 1 solenoid valve there. canister is back of car under the trunk. remove the 3 13mm nuts and drop plastic cover, you'll see it. when you replace those parts blow the line for the purge valve. the carbon broke up causing purge issue & carbon is most likly causing purge valve to fail. you can pinch off before purge valve and run test to verfy 1 fault goes away.
==
My bet is that your charcoal cannister for the fuel overflow is bad also and is ..
causing your purge valve to fail and throw a code. Clear the CEL via VAG after changing the purge valve but if the same codes come back next time I would change the charcoal cannister.
Actually I was told that it gets filled up from the over flow when you top off the tank<more>
When they changed my charcoal cannister at 80k miles he said the difference in weight between the new and old was incredible because of the all the gas that got absorbed into the charcoal. Got rid of my EVAP codes once and for all. Topping off your tank is a big no no in my book after that.
06-27-2009, 08:29 PM
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Partial answer, at least: stolen gas cap!
The Evap Emission Control System should have been a tip-off.
I'm worried, at 125k miles, that the "Catalyst System Efficiency Below Threshold" may persist. Then, I'm off to find the cheapest, decent catalytic converters, I'm afraid....
I'm worried, at 125k miles, that the "Catalyst System Efficiency Below Threshold" may persist. Then, I'm off to find the cheapest, decent catalytic converters, I'm afraid....
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