Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
Your car's engine is making a knocking noise because a part that helps create the spark for the engine is not working right.
The engine control module (ECM) has detected excessive knocking in the engine due to a malfunctioning ignition coil.
The P137A code indicates that the ECM has detected a condition known as 'super knocking,' which is a severe form of engine knock. This is often caused by a defective ignition coil that fails to provide the necessary spark to the engine cylinders, leading to improper combustion and knocking.
• Engine knocking noise
• Poor engine performance
• Check Engine Light illuminated
• Defective ignition coil
• Faulty spark plugs
• Wiring issues in the ignition system
ECM: Engine Control Module
Ignition Coil: A component that converts battery voltage into a high voltage spark
• Use an OBD-II scanner to confirm the code.
• Inspect the ignition coils for damage or wear.
• Check the spark plugs and wiring for issues.
• Replace the defective ignition coil.
• Replace faulty spark plugs.
• Repair or replace damaged ignition wiring.
• OBD-II scanner
• Multimeter
• Socket set
$150 - $400
Moderate
• Toyota Camry
• Honda Accord
• Ford F-150
• Regularly inspect ignition coils.
• Replace spark plugs as per maintenance schedule.
• Keep the ignition system clean and dry.
Engine Performance
• Avoid driving with a knocking engine to prevent damage.
• Have the vehicle inspected by a professional mechanic.
Check if the ignition coil is covered under the vehicle's powertrain warranty.
This code has been associated with vehicles experiencing severe engine knock due to ignition system failures.
High – Prolonged driving with this issue can cause severe engine damage.
Driving with an engine knock can lead to engine failure and is unsafe.
• Engine at operating temperature
• Vehicle in a controlled environment
The ignition coil is typically located on top of the engine, connected to the spark plugs.
Q: Can I drive with a P137A code?
A: It's not recommended as it can cause severe engine damage.
Q: How can I prevent this issue?
A: Regular maintenance of the ignition system can help prevent this problem.
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Universal · Digital multimeter
A solid entry-level multimeter for voltage, continuity, resistance, and basic electrical troubleshooting.
Helpful for checking voltage drops, grounds, and basic circuit health when modules are not communicating.
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Universal · Wire connectors and repair kit
Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
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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.