We have a 2009 1.4 VTi on 75k, it is rough at idle and the revs hunt. Unfortunately, the car has been off the road for a while and I don't know anything about the back story except that it has a full service history. I have given it a service anyway but that has not helped.
It has a code for the Cat of P0420. Obviously it could be the Cat, but it isn't running right and so I want to address that before spending hundreds on a new Cat.
Any pointers on where to start with these engines? Do they suffer from sticking EGR valves or anything that causes them to struggle at idle?
I have access to DiagBox, so I can get the live data if anything needs checking or resetting. Cheers.
Peugeot 207 rough idle and P0420
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mickthemaverick
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Re: Peugeot 207 rough idle and P0420
You may find this post helpful: viewtopic.php?p=590355#p590355
I used to be indecisive, now I'm not so sure!
I used to ride on two wheels, but now I need all four!
I used to ride on two wheels, but now I need all four!
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MarkandCath
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Re: Peugeot 207 rough idle and P0420
Thanks Mick.mickthemaverick wrote: 25 Oct 2025, 22:03 You may find this post helpful: viewtopic.php?p=590355#p590355
That video on how the CAT works and how to understand the live data is very helpful. I will plug it in early next week and find out what is happening.
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ozvtr
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Re: Peugeot 207 rough idle and P0420
That sounds like a vacuum leak. Does it run fine otherwise?MarkandCath wrote: 25 Oct 2025, 21:05 We have a 2009 1.4 VTi on 75k, it is rough at idle and the revs hunt.