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996 C2 P0448 wont clear.

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2 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis

THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCH996 C2 P0448 wont clear.

Leading reported evidence

Replace every sensor related

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

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Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed · Original poster
Ive already changed every sensor related to the evap system including the tank�s vent valve and even the canister itself.
Original post Read captured discussion
996 C2 P0448 wont clear.

Frequently discussed work

Clean will cure a stuck valve

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

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Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion
Sometimes cleaning will cure a stuck valve.
Original post Read captured discussion
996 C2 P0448 wont clear.

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Leading evidence: 'Replace every sensor related' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Clean will cure a stuck valve' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.

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1 matching discussions · 2 captured posts examined · 0 partial discussions

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Clean will cure a stuck valve

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion
Sometimes cleaning will cure a stuck valve.
Original post Read captured discussion
996 C2 P0448 wont clear.

Replace vent valve and are still getting the code

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion
If you replaced the vent valve and are still getting the code then it's possible that the wires that are shorted, or something's wrong with the computer.
Original post Read captured discussion
996 C2 P0448 wont clear.

Run crappy

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
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Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion
This valve won't effect how the car runs so I'm thinking that maybe the problem is that the purge valve is stuck open and the computer is mistakenly pointing toward the vent valve, a stuck purge valve will make it run crappy.
Original post Read captured discussion
996 C2 P0448 wont clear.

Frequently discussed actions (4)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

Clean will cure a stuck valve

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion
Sometimes cleaning will cure a stuck valve.
Original post Read captured discussion
996 C2 P0448 wont clear.

Replace every sensor related

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that performed work without a confirmed outcome: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed · Original poster
Ive already changed every sensor related to the evap system including the tank�s vent valve and even the canister itself.
Original post Read captured discussion
996 C2 P0448 wont clear.

Replace vent valve and are still getting the code

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion
If you replaced the vent valve and are still getting the code then it's possible that the wires that are shorted, or something's wrong with the computer.
Original post Read captured discussion
996 C2 P0448 wont clear.

Run crappy

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion
This valve won't effect how the car runs so I'm thinking that maybe the problem is that the purge valve is stuck open and the computer is mistakenly pointing toward the vent valve, a stuck purge valve will make it run crappy.
Original post Read captured discussion
996 C2 P0448 wont clear.

Coverage and how to read this overview

Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.

2 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

Rennlist: 1 discussions

0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.

0 acknowledgements have no verified action link; they do not establish a repair result.

Generation: 20261026T222516Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Hi guys. New to the forums but old reading your solutions. This time i need some input. My 2001 996 C2 has a P0448 code (Evaporative Emission Control System Vent Valve/Solenoid Circuit Shorted). Ive already changed every sensor related to the evap system including the tank�s vent valve and even the canister itself. There is no other code but the car still idles and runs like crap. Any help will be appreciated.

POST 2Original post

If you replaced the vent valve and are still getting the code then it's possible that the wires that are shorted, or something's wrong with the computer. This valve won't effect how the car runs so I'm thinking that maybe the problem is that the purge valve is stuck open and the computer is mistakenly pointing toward the vent valve, a stuck purge valve will make it run crappy. The purge valve is the one that allows intake vacuum to flow through the EVAP system. I don't know exactly where in the engine compartment it's mounted. Find it and blow through it to see if it flows air, it should only flow when commanded by the computer, generally during cruising conditions. Sometimes cleaning will cure a stuck valve.

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