vw passat 2.0 petrol - running rough

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Fri 30 Dec 2011 11:26
vw passat 2.0 petrol - running rough - trickydicky

90000 miles had new coil packs & plugs fitted by garage still not running right they say it is showing a fault code p0420;-catalyst system cylinder bank 1 operation too low.dont want to fit a new cat if not shure of a cure.running rough and using a lot of fuel

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Fri 30 Dec 2011 13:34
vw passat 2.0 petrol - running rough - elekie&a/c doctor

This fault code relates to a cat efficiency fault,possibly due to a prevoius fault with an engine misfire.It will not cause an engine running problem.If the engine is still running rough ,I would suggest the problem is elsewhere.hth

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Fri 30 Dec 2011 14:46
vw passat 2.0 petrol - running rough - Med

Hi, i've got a VW Passat 2.0tfsi - i had the same problem and tried a lot of things, i also had a similar fault code as yours.

Have you tried the Crankcase Breather or another name for it is the pressure relief valve.....? You can buy it from VW directly with the gasket for an extra cost...

The part number is: 06F129101P make sure you do ask for the gasket.

Let me know if this helped? :)

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Mon 2 Jan 2012 11:38
vw passat 2.0 petrol - running rough - trickydicky

forgot to say it was a 05.will have a look at the crankcase breather and let you know if that cures thanks

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