Question

1999 Nissan Frontier 4wd 3.3l, can a bad knock sensor affect NOx levels? Cannot pass CA emissions but, everything else seems to check out okay

Answer 1

No. A knock sensor code on a Nissan is common,everyone with a Nissan has this code in there, What effects the Nox is the EGR being plugged or the transducer not working,or the EGR not woring itself

Answer 2

P0325 NISSAN - Knock Sensor Circuit Malfunction

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