What causes P1420 on a Honda?

Aged NOx adsorptive catalyst saturated beyond recovery Sulfur contamination from high-sulfur fuel Exhaust leak ahead of the catalyst skewing the monitor Extended short-trip driving preventing catalyst regeneration Faulty catalyst monitor sensor or ECM calibration

How do I fix P1420 on a Honda?

Inspect the exhaust ahead of the catalyst for leaks first Check for sulfur-heavy fuel history and advise top-tier fuel Run a sustained highway drive cycle to allow regeneration Compare pre- and post-catalyst sensor behavior with an HDS scan tool Replace the NOx adsorptive catalyst if efficiency stays below limit

P1420 NOx Adsorptive Catalyst System - Efficiency Below Limit

Q: What does P1420 mean on a Honda?

P1420 — NOx Adsorptive Catalyst System - Efficiency Below Limit. Applies to Insight, Civic HX.

Category: Powertrain - Auxiliary Emissions Controls
Severity: Check Engine Light
Applies to: Insight, Civic HX

What does P1420 mean on a Honda?

P1420 — NOx Adsorptive Catalyst System - Efficiency Below Limit. This Honda-enhanced code applies to Insight, Civic HX.

Common causes of P1420

Aged NOx adsorptive catalyst saturated beyond recovery
Sulfur contamination from high-sulfur fuel
Exhaust leak ahead of the catalyst skewing the monitor
Extended short-trip driving preventing catalyst regeneration
Faulty catalyst monitor sensor or ECM calibration

How to fix P1420

Inspect the exhaust ahead of the catalyst for leaks first
Check for sulfur-heavy fuel history and advise top-tier fuel
Run a sustained highway drive cycle to allow regeneration
Compare pre- and post-catalyst sensor behavior with an HDS scan tool
Replace the NOx adsorptive catalyst if efficiency stays below limit