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P0420 code on a 2001 INFINITI -qx4

I have service engine soon light. Failed emission inspection and showed codes p1140 and p0420

Vehicle: 2001 infinity qx4 3500 v6
asked Mar 22, 2013 by anonymous

1 Answer

You should start by fixing the P1140 code. Sometimes the code is caused by dirty engine oil.

P1140 INFINITI - Intake Valve Timing Control Performance Bank 1

Read more: http://engine-codes.com/p1140_infiniti.html

P0420 INFINITI - Catalyst System Efficiency Below Threshold Bank 1

Read more: http://engine-codes.com/p0420_infiniti.html

answered Mar 22, 2013 by OBDIITech (2,507 points)

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