Back to 1998 Acura CL

1998 ACURA CL

2.2L I4FWDAUTOMATICgas
5 active safety recalls on this vehicle — view recalls
Repairs0Labor472Torque2465Fluid6DTC657Battery0Maintenance0Recalls5
P1166low severityPowertrain

HO2S Bank 1 Sensor 1 Heater Circuit Fault

on 1998 Acura CL 2.2L I4 · FWD

What this code means

The heater circuit in the upstream O2 sensor has a malfunction.

Symptoms

  • CEL
  • Poor cold-start economy
  • Extended warm-up
  • Increased emissions

Common causes

  • Failed heater element
  • Blown fuse
  • Open/short wiring
  • Corroded connector

Diagnostic steps

  1. Test heater resistance
  2. Check fuse
  3. Inspect wiring
  4. Test PCM relay

Repair notes

Replace O2 sensor or repair heater circuit.

Other Powertrain codes on this vehicle

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