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 detected a problem with the way cylinder number 4 is firing up when you start the engine. It's like one of the spark plugs isn't doing its job properly, causing the engine to stumble or shake.
The P1348 code indicates that the engine control module (ECM) has detected a misfire in cylinder 4 during the engine start sequence.
When the ECM detects an irregularity in the firing of cylinder number 4 during engine startup, it triggers the P1348 code. This can be due to a variety of issues such as a faulty spark plug, ignition coil, or fuel injector in cylinder 4, or even a mechanical issue like low compression.
• Rough engine start
• Check Engine Light on
• Poor engine performance
• Engine shaking or vibrating
• Decreased fuel efficiency
• Faulty spark plug in cylinder 4
• Defective ignition coil for cylinder 4
• Clogged or faulty fuel injector in cylinder 4
• Low compression in cylinder 4
• Vacuum leak affecting cylinder 4
ECM: Engine Control Module
Misfire: Failure of the air/fuel mixture in the cylinder to ignite properly
• Use an OBD-II scanner to confirm the P1348 code.
• Inspect the spark plug in cylinder 4 for wear or damage.
• Check the ignition coil for cylinder 4 for proper operation.
• Examine the fuel injector for cylinder 4 for clogs or faults.
• Perform a compression test on cylinder 4.
• Replace the spark plug in cylinder 4 if faulty.
• Replace the ignition coil for cylinder 4 if defective.
• Clean or replace the fuel injector for cylinder 4.
• Repair any vacuum leaks affecting cylinder 4.
• Address any mechanical issues such as low compression.
• OBD-II scanner
• Spark plug socket and wrench
• Multimeter
• Compression tester
• Fuel injector cleaning kit
$100 - $500
Moderate
• Toyota Camry
• Honda Accord
• Ford Focus
• Regularly replace spark plugs as per maintenance schedule.
• Use quality fuel to prevent injector clogs.
• Perform regular engine tune-ups.
Engine Performance
• Avoid driving the vehicle until the issue is fixed to prevent further damage.
• Schedule a service appointment with a qualified mechanic.
Check vehicle warranty for coverage on ignition components.
The P1348 code has been associated with ignition system issues in certain models, often linked to spark plug or coil failures.
Moderate – Address promptly to avoid potential engine damage.
Ignoring this code may lead to increased emissions and potential engine damage.
• Engine at operating temperature
• Engine starting sequence
Cylinder 4 is typically located on the engine block, depending on the engine layout.
Q: Can I drive with a P1348 code?
A: It's not recommended to drive with a P1348 code as it may cause further engine damage.
Q: How can I prevent a P1348 code?
A: Regular maintenance, including timely replacement of spark plugs and ignition components, can help prevent this code.
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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.