OBD Guide

P28A4

Cylinder 6 Ion Current Sense Circuit

P28A4 is an OBD-II diagnostic trouble code meaning: Cylinder 6 Ion Current Sense Circuit. Common causes: open or short circuit in the sensor circuit, ion current sensor malfunction. Estimated repair cost: $28–89.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$28–89 (est.)

Symptoms

  • Unstable engine operation
  • Increased fuel consumption
  • Check Engine Light Illuminates
  • Reduced engine power
  • Possible misfires

Causes

  • Open or short circuit in the sensor circuit
  • Ion current sensor malfunction
  • Connector problems or contact corrosion
  • Engine control unit malfunction
  • Mechanical problems in the cylinder (rare)

How to Fix

  1. Check the integrity of wiring and connectors
  2. Check the resistance of the ion current sensor
  3. Inspect contacts for corrosion
  4. If necessary, replace the ion current sensor
  5. Check the operation of the engine control unit

Related codes

Error P28A4 by Vehicle Brand

FAQ

What does the P28A4 code mean?

P28A4 is an OBD-II diagnostic trouble code that indicates: Cylinder 6 Ion Current Sense Circuit

What causes a P28A4 error code?

The most common causes of P28A4 include: Open or short circuit in the sensor circuit; Ion current sensor malfunction; Connector problems or contact corrosion; Engine control unit malfunction.

How do I fix a P28A4 diagnostic trouble code?

To fix P28A4: Check the integrity of wiring and connectors. Check the resistance of the ion current sensor. Inspect contacts for corrosion. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P28A4?

Yes, but get it checked soon

How much does it cost to fix P28A4?

The estimated repair cost for P28A4 is $28–89. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat