7 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHDreaded P0446
Reported or suspected cause
fuel door lock actuator was shorting
Reported cause
No successful repair reported for this finding.
1
Identified cause
0
Suspected cause
0
Reported fixes
Read evidence and context
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 report identifying a cause
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.
Reported cause
Yea, I have had that fuse blow before, but as I recall it didn't cause an evap code, it caused a code in the "alarm system" and was due to the fuel door lock actuator was shorting...
Leading evidence: 'fuel door lock actuator was shorting' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'fuel door lock actuator was shorting' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Check 7.5amp fuse' (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.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
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 report identifying a cause
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.
Reported cause
I had a p0446 one time ( customer car) that turned out to the fuel tank pressure sensor on top of the tank.....very unlikely it is the DME...
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 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.
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 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
Are there any symptoms, like not able to fill car gas tank to 100% full...?
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 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
The fuel door wouldn't lock/unlock, also was causing unable to fill the tank properly/quickly due to no power to the tank vent valve ( also located on top of the fuel tank..)
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
The fuel door wouldn't lock/unlock, also was causing unable to fill the tank properly/quickly due to no power to the tank vent valve ( also located on top of the fuel tank..)
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
Aside from any leaks, the pressure sensor monitors for expected pressure changes/or non-expected pressure changes due to leaks or purging of the fumes, but if the sensor is its self faulty, then the DME will receive erroneous reports on the evap system and flag a fault code....
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
Aside from any leaks, the pressure sensor monitors for expected pressure changes/or non-expected pressure changes due to leaks or purging of the fumes, but if the sensor is its self faulty, then the DME will receive erroneous reports on the evap system and flag a fault code....
These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.
fuel door lock actuator was shorting
No successful repair reported for this finding.
1
Identified cause
0
Suspected cause
0
Reported fixes
Read evidence and context
Discussions that report identifying a cause
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.
Reported cause
Yea, I have had that fuse blow before, but as I recall it didn't cause an evap code, it caused a code in the "alarm system" and was due to the fuel door lock actuator was shorting...
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.
7 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: 20261026T091943Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
1999 996 Cabriolet. Been battling P0446 for awhile - new purge valve, new gas gap, smoke test sat. Dealer now convinced it's a faulty DME. While I wait for them to order the CORRECT DME, how likely this is actually the cause of P0446?
Its almost never the dme. Lots of info if u google the code.
lots of causes from the purge valve, gas cap, blocked purge line, bad charcoal canister, down stream o2 sensors and vacuum leaks.
btw, not sure how a bad dme could even cause this issue but im sure the dealer has a flow chart and at the end of the line it says "replace dme"
if the will refund the cost of a new dme if it doesnt work, let them throw parts at it, i guess.
I had a p0446 one time ( customer car) that turned out to the fuel tank pressure sensor on top of the tank.....very unlikely it is the DME...
I certainly would "try" a pressure sensor before condemning the DME... ( DME's are $$$$ ) ....
po446 iirr, is more or less a universal incorrect evap voltage error code.
Are there any symptoms, like not able to fill car gas tank to 100% full...?
Here's an easy test to see if there is any voltage in the evap system control cicuit. In a quite garage, remove gas cap and push open the flapper valve with your finger while listening for the 'click' of the reed switch in the filler neck. It makes a distinct click noise 1/2 second after every time its opened/closed, easily heard in a quite garage setting. If no click is heard, check the 7.5amp fuse. for some strange reason only Porsche could answer, evap fuse is listed as 'Telephone' not evap system. Its a 7.5 amp brown fuse in E6 position iirr....
jmo
Yea, I have had that fuse blow before, but as I recall it didn't cause an evap code, it caused a code in the "alarm system" and was due to the fuel door lock actuator was shorting...
The fuel door wouldn't lock/unlock, also was causing unable to fill the tank properly/quickly due to no power to the tank vent valve ( also located on top of the fuel tank..)
Yes the "Click test" will verify power to that circuit, it is actually the vent valve/solenoid on top of the tank that makes the "click"...
But iirr it didn't set a code in the "DME" only in the "alarm control unit" ..
Code P0446 is a generic evap code, meaning something wrong with the evap system...
It is a sealed system with " expected pressures" that are sensed by the pressure sensor and reported to the DME..
ANY leak in the whole system can cause the code,( purge valve being the most common........ or fuel cap) but literally any leak anywhere can cause the code...
Aside from any leaks, the pressure sensor monitors for expected pressure changes/or non-expected pressure changes due to leaks or purging of the fumes, but if the sensor is its self faulty, then the DME will receive erroneous reports on the evap system and flag a fault code....
This is a source reference. Confirm exact model applicability in the original material.
