Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer has detected a problem with the electrical signal coming from cylinder 6. It's like when a light bulb is too bright because too much electricity is going through it.
The ion current sense circuit monitors the ionization current in the combustion chamber of cylinder 6. A 'high' signal indicates excessive voltage or current in the circuit.
The P28A7 code is triggered when the Engine Control Module (ECM) detects a voltage level in the ion current sense circuit for cylinder 6 that is higher than the expected range. This could indicate a short circuit, a faulty sensor, or an issue with the wiring.
• Check engine light on
• Engine misfires
• Poor fuel economy
• Faulty ion current sensor
• Short circuit in the wiring
• Faulty ECM
ECM: Engine Control Module, the computer that controls engine functions.
Ion Current Sensor: A sensor that detects the ionization in the combustion chamber to monitor combustion quality.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections for cylinder 6.
• Test the ion current sensor for proper operation.
• Replace faulty ion current sensor.
• Repair or replace damaged wiring.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$150 - $500
Moderate
• BMW 3 Series
• BMW 5 Series
• BMW X5
• Regular maintenance checks
• Ensure proper engine tuning
• Use high-quality fuel
Sensor Issue
• Avoid driving the vehicle until repaired to prevent further damage.
• Consult a professional mechanic for accurate diagnosis.
Check with your vehicle manufacturer for specific warranty coverage on engine sensors.
This code is relatively uncommon and typically associated with specific models known for advanced ignition systems.
Moderate – Should be addressed soon to prevent potential engine damage.
Driving with a misfiring engine can lead to increased emissions and potential engine damage.
• Engine at operating temperature
• Vehicle stationary
The ion current sensor for cylinder 6 is typically located near the ignition coil or spark plug of cylinder 6.
Q: Can I drive my car with this code?
A: It's not recommended to drive with this code as it may lead to engine damage.
Q: Is this a common issue?
A: This issue is not very common and usually occurs in vehicles with advanced ignition systems.
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Fitment Required · Vehicle-fitment part
Commonly relevant for misfire, ignition-efficiency, and some drivability-related repairs.
Misfire and ignition-related faults commonly involve spark plugs as part of the repair path.
Check the correct plug type, gap, and engine application for your vehicle.
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Fitment Required · Vehicle-fitment part
Relevant when the fault points toward ignition-coil performance or cylinder-specific ignition issues.
Some ignition faults involve coil performance or cylinder-specific coil problems.
Match the coil to your engine and confirm the failed component before ordering.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.