P28B1

Cylinder 9 Ion Current Sense Circuit Range/Performance

Severity

⚠️ Medium

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$17–67 (est.)

Symptoms

Unstable engine operation
Power Loss
Increased fuel consumption
Check Engine Light Illuminates
Possible misfire in cylinder 9

Causes

Open or short circuit in the ion current circuit
Malfunction of the spark plug of the 9th cylinder
Problems with the ignition coil
Low cylinder compression
Engine control unit malfunction

How to Fix

Check the integrity of the ion current circuit of the 9th cylinder
Replace the spark plug in cylinder 9
Check and, if necessary, replace the ignition coil
Measure compression in cylinder 9
Diagnose the engine control unit

Related codes

P28B0 P28B2 P0309