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 thinks the engine is getting too hot too quickly. It's like when you run too fast and start sweating a lot, the car's engine is heating up faster than it should.
The engine control module (ECM) monitors the rate of change in the engine coolant temperature. If it detects that the temperature is increasing too rapidly, it triggers this code.
The P3198 code is set when the ECM detects an excessive rate of temperature increase in the engine coolant. This could be due to various factors, such as a malfunctioning thermostat, low coolant levels, or a faulty temperature sensor. The rapid increase in temperature may indicate a cooling system issue that needs attention.
• Engine overheating
• Check engine light on
• Poor engine performance
• Faulty thermostat
• Low coolant level
• Malfunctioning coolant temperature sensor
ECM: Engine Control Module, the computer that manages engine functions
Thermostat: A device that regulates the flow of coolant to maintain engine temperature
• Check coolant level and refill if necessary
• Inspect the thermostat for proper operation
• Test the coolant temperature sensor
• Replace the thermostat if faulty
• Repair any leaks in the cooling system
• Replace the coolant temperature sensor if defective
• OBD-II scanner
• Coolant pressure tester
• Multimeter
$150 - $400
Moderate
• Toyota Camry
• Honda Accord
• Ford Focus
• Regularly check coolant levels
• Perform routine cooling system maintenance
• Replace the thermostat at recommended intervals
Engine Performance
• Do not drive the vehicle if it is overheating
• Get the cooling system checked by a professional
Check with your vehicle manufacturer to see if cooling system components are covered under warranty.
This code has been associated with issues in vehicles with aging cooling systems or those that have not been maintained regularly.
High – Driving with an overheating engine can cause severe damage.
Ignoring this code can lead to engine failure, which may result in costly repairs and safety hazards.
• Engine at operating temperature
• Vehicle idling or under load
The coolant temperature sensor is typically located near the thermostat housing on the engine.
Q: Can I drive with a P3198 code?
A: It's not recommended to drive with this code, as it indicates potential overheating, which can damage the engine.
Q: What happens if I ignore the P3198 code?
A: Ignoring this code can lead to engine overheating, which may cause severe engine damage and expensive repairs.
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Fitment Required · Vehicle-fitment part
Relevant when coolant-temperature and warm-up faults indicate a thermostat-related issue.
Coolant-temperature and warm-up faults often lead to thermostat testing and replacement.
Thermostats are vehicle-specific and should be matched by engine and housing style.
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.