P0420 fault code anyone else had this ?
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P0420 fault code anyone else had this ?
The bug wagon threw up a cel code yest found out today it's p0420
Spoke to the guy who scanned it for me he said check the vacuum pipes first as I have just had a major service and maybe a mech had dislodged a pipe what else could it be because I can't hear any air loss from them cheers
Spoke to the guy who scanned it for me he said check the vacuum pipes first as I have just had a major service and maybe a mech had dislodged a pipe what else could it be because I can't hear any air loss from them cheers
#2
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P0420 is an inefficient CAT code.
Is the car fitted with a sportcat or decat ?
Is the car fitted with a sportcat or decat ?
#6
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Did you solve this? I have a STI with a prodrive sports cat and the same code. would it be the sport cat that is causing this or could it be something else like the front o2 sensor?
#7
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I have a 51 plate bugeye wagon and the CEL came on last Saturday whilst going up the M1 (it remained solid which suggested it wasn't detrimental). I got off at the next available junction and checked the obvious things. It was evident I'd let the oil level slip - suffice to say it was short of oil. I got the car to the next available services and chucked in some 10w40, and then decided to return home just in case something more serious was wrong.
I purchased an OBDII reader that same day with a view to checking the code and seeing if it was something I could sort myself - would've expected the oil light to be illuminated for problems with oil. However, before the reader arrived, and after a few days of normal journeys, the CEL went out, so on the surface it appears that the [lack of] oil [pressure ?] triggered the CEL, and the ECU corrected itself as a result of me correcting the oil level.
Still curious about what code the ECU actually generated I plugged in the OBDII reader and it had recorded a P0420 fault code. Not sure how low oil would trigger that really (guess it might not actually have been the oil at all ?).
Anyway, having done a search on scoobynet it seems that people have encountered the P0420 (and other related codes) as a result of a number of different causes, but one of the most frequent that keeps coming up is a faulty neutral position switch on the gearbox eg:
https://www.scoobynet.com/general-te...2-and-4-a.html
I purchased an OBDII reader that same day with a view to checking the code and seeing if it was something I could sort myself - would've expected the oil light to be illuminated for problems with oil. However, before the reader arrived, and after a few days of normal journeys, the CEL went out, so on the surface it appears that the [lack of] oil [pressure ?] triggered the CEL, and the ECU corrected itself as a result of me correcting the oil level.
Still curious about what code the ECU actually generated I plugged in the OBDII reader and it had recorded a P0420 fault code. Not sure how low oil would trigger that really (guess it might not actually have been the oil at all ?).
Anyway, having done a search on scoobynet it seems that people have encountered the P0420 (and other related codes) as a result of a number of different causes, but one of the most frequent that keeps coming up is a faulty neutral position switch on the gearbox eg:
https://www.scoobynet.com/general-te...2-and-4-a.html
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Lambda sensor most likely. These get coked up on all modern cars.
Take it out, submerge it in a cup of diesel over night and see if it cures the issue.
Take it out, submerge it in a cup of diesel over night and see if it cures the issue.
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