Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the heater that helps start engine number 3 in a diesel car. It's like when a toaster's wire is broken and it can't heat up.
The P0673 code indicates an issue with the electrical circuit for the glow plug in cylinder number 3 of a diesel engine.
Glow plugs are used in diesel engines to heat the air in the cylinders to a temperature that allows for efficient combustion. The P0673 code is triggered when the Engine Control Module (ECM) detects an open circuit or a fault in the glow plug circuit for cylinder number 3.
• Difficulty starting the engine
• Rough engine idle
• Increased exhaust smoke during startup
• Faulty glow plug
• Damaged glow plug wiring or connector
• Faulty glow plug control module
Glow Plug: A device used to heat the air in a diesel engine's cylinders to aid in starting.
ECM: Engine Control Module, the computer that controls engine functions.
• Inspect the glow plug for cylinder 3 for damage or wear.
• Check the wiring and connectors for cylinder 3's glow plug circuit.
• Test the glow plug control module for proper operation.
• Replace the faulty glow plug.
• Repair or replace damaged wiring or connectors.
• Replace the glow plug control module if necessary.
• Multimeter
• Socket set
• Diagnostic scanner
$100 - $300
Moderate
• Ford F-250
• Chevrolet Silverado
• Dodge Ram 2500
• Regularly inspect glow plugs and wiring.
• Use quality diesel fuel.
• Perform routine engine maintenance.
Sensor Issue
• Have the vehicle inspected by a professional if you experience starting issues.
• Avoid prolonged cranking of the engine to prevent battery drain.
Check with your vehicle manufacturer for warranty coverage on engine components.
Glow plug circuit issues have been common in diesel engines, especially in colder climates where glow plugs are essential for starting.
Moderate – Address the issue to avoid starting problems and potential engine damage.
Driving with a faulty glow plug can lead to increased emissions and starting difficulties, which may not comply with local environmental regulations.
• Cold engine start
• Ambient temperature below freezing
The glow plug for cylinder 3 is located on the engine block, typically near the third cylinder from the front of the engine.
Q: Can I drive with a P0673 code?
A: It's possible to drive, but you may experience starting issues and increased emissions. It's best to fix the issue soon.
Q: How do I know if my glow plug is bad?
A: Symptoms include difficulty starting the engine, rough idling, and increased smoke during startup.
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