# P0420 (TW Catalyst SYS - B1)



## MD Sariful Islam (Feb 9, 2020)

Hi,
This is Sariful. I own a Nissan xtrail 2013. Last few days I am having problem with P0420 code. Practically, In idle rpm, sometimes the car tends to be stopped and idle speed also fluctuating bit . In high speed which is 70 to 90 km/h the car jurking for a while. But this is not regularly. Sometimes I can feel it after 100 km also. 
Just after jurking that code come out 

If anybody have experience with same issue this please share with me.
Thnks in advance


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## rogoman (Dec 16, 2004)

A P0420 fault code can be caused by any of the following conditions:

● Three way catalyst (manifold) has failed.
● Exhaust pipe leaks (holes or gasket leaks).
● Intake system vacuum leaks.
● Bad fuel injector(s).
● Fuel injector leaks.
● Spark plug fouling.

From your description of driveability problems, I would initially suspect a problem with one or more fuel injectors being dirty or possibly leaking. I would first try a *good* fuel injection cleaner like Techron, Redline SL-1 or BG products 44K through the system; give the cleaner about a week or two to do it's job. 
A good way to test leaking injectors is to tee-in a temporary fuel pressure gauge between the fuel feed hose and the fuel rail. Turn the ignition key to the run position but *DO NOT TRY TO START THE ENGINE*. The fuel pressure reading should initially be around 51 psi. Now watch the gauge for a rapid drop in pressure which could indicate a leaking injector(s).

If your vehicle has at least 100,000 MI and you're having the driveability problems that you've described, a good option is to replace all the fuel injectors with new OEM or reman'd OEM components.


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## Afaza (Jul 8, 2020)

Hei


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## Afaza (Jul 8, 2020)

CODE PO420, PO335 and PO725, can some one helpe me please, i have Nissan x-trail 2002 automat Bensin


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## rogoman (Dec 16, 2004)

Afaza said:


> CODE PO420, PO335 and PO725, can some one helpe me please, i have Nissan x-trail 2002 automat Bensin


A P0420 fault code can be caused by any of the following conditions:

● Three way catalyst (manifold) has failed.
● Exhaust pipe leaks (holes or gasket leaks).
● Intake system vacuum leaks.
● Bad fuel injector(s).
● Fuel injector leaks.
● Spark plug fouling.

A P0335 fault code can be caused by any of the following conditions:

● Harness or connectors (The sensor circuit is open or shorted). Loose connectors.
● Bad crankshaft position sensor.
● A damaged signal plate (chipped signal plate gear tooth). The signal plate is mounted on the crankshaft torque plate.

A P0725 fault code can be caused by any of the following conditions:

● Harness or connectors (The sensor circuit is open or shorted). Loose connectors.
● Bad speed sensor.
● Dirty or insufficient transmission fluid.


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