11 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHFault code help P0402 & P0403
Leading reported evidence
Reset codes and they did not come back
Performed · outcome unconfirmed
No successful repair reported for this finding.
0
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0
Unsuccessful attempts
1
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Performed · outcome unconfirmed · Original poster
I reset the codes and they did not come back but it bother me not fixing it properly!
Leading evidence: 'Reset codes and they did not come back' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Reset codes and they did not come back' (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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Suggestion
Other than having slightly lower energy than 100% gasoline, there are many benefits to running a 10% ethanol fuel.
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11 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
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PO402-Porsche fault code 40. Cat Conv effieiency Bank 1
PO403-Porsche fault code 45. Cat Conv efficiency Bank 2
What are these codes? Any one know how to fix them? I reset the codes and they did not come back but it bother me not fixing it properly!
Thanks in advance.
M
Perhaps you mean P0420 (DTC 40) and P0430 (DTC 45)?
P0420 TWC conversion, bank 1 - above limit
Possible fault cause:
- Oxygen sensor ahead of and after TWC exchanged
- Valve lift fault
- Aged oxygen sensor after TWC
- TWC faulty
P0430 TWC Conversion, Bank 2 - Above Limit
Possible fault cause
- Oxygen sensor ahead of and after TWC exchanged
- Valve lift fault
- Aged oxygen sensor after TWC
- TWC faulty
Very strange if it is two ages O2 sensors - usually they go one at a time.
How many miles? and since someone else brought it up... Did someone put in the wrong fuel type?
I had these same codes on my Jag XJR, a leak will set them off. O2 sensor measured too much O2! My cat had a crack. I had it welded and the codes never came back. Did you mess with the exhaust recently?
Not sure what you are implying? It is virtually impossible (illegal) in the state of Colorado to sell (buy) gas without ethanol...I have been running it for 4 years.
These codes were direct copy from Durametric Scanner.
PO402-Porsche fault code 40. Cat Conv effieiency Bank 1
PO403-Porsche fault code 45. Cat Conv efficiency Bank 2
The car only has 26000mi. I was using Shell V-power, which is the closest gas station by the track. That day, I had 2.5hours track time. Car ran good at the track. Eng lite came on when I drove home.
Now, the light did not come back on. If I continue tracking the car, will I damage the engine?
Here where I live (Mississauga, Canada), you can choose- I now use Shell Vpower 91, no Ethanol.
It sucks if in Colorado fuel with no Ethanol is illegal.
I read a link in a recent fuel discussion, that shows damage to several internal
parts (including Cat converters, hoses and some plastics in the fuel injection
system) that are caused by use of Ethanol.
It also mentions that it affects older cars more than new.
John
Found it:
http://www.fuel-testers.com/ethanol_...ecautions.html
I also used to use Sunoco 94 with Ethanol, but after this info, I switched to Shell 91 no Ethanol.
John
Cat efficiency code usually means bad cats, but it is odd that both codes would pop up simultaneously; that speaks to something on the intake side, or maybe the computer. Depending on your driving, it could take a while for a CEL to come back on.
10% ethanol based fuel will not harm your engine in anyway whatsoever. It is all a myth. Other than having slightly lower energy than 100% gasoline, there are many benefits to running a 10% ethanol fuel.
This is a source reference. Confirm exact model applicability in the original material.
