Experiencing high exhaust temperature in your vehicle can throw you into concerns seeing reduced engine performance and increased emissions.
Fortunately, there are several steps you can take to address this issue and bring the exhaust temperature back to optimal levels.
What does high exhaust system temperature mean, and how to fix high exhaust temperature? This post will explore effective methods and practical tips to help you solve this problem.
What Causes High Exhaust Temperature?
Low-Quality Fuel
Low-quality fuel or poor fuel treatment will lead to incomplete combustion.
Besides, when the openings in the valve nozzles are enlarged, excessive fuel can go through the combination chamber.
These will result in unburned fuel entering the exhaust system, raising the exhaust gasses’ temperature.
Faulty Fuel Pump
The fuel pump supplies fuel to the engine. If your fuel pump goes out or gets damaged, there may be insufficient fuel or inconsistent pressure.
This can create a high-pressure fuel supply pump and a lean fuel-air mixture. Thus, it may force the engine to run hotter with increased exhaust temperature.
Faulty Valves
Valves control air-fuel intake and exhaust. If faulty, they may not seal or open/close correctly. It will disrupt combustion, leading to the incomplete burning of fuel.
Unburned and partially burned fuel will lead to temperature increases.
Faulty Injectors
Injectors deliver fuel to the diesel motor combustion chamber. If your car has a faulty or leaky fuel injector, it may spray fuel unevenly or at the wrong angle, causing uneven fuel distribution.
This leads to incomplete burning, higher exhaust temperatures, and reduced fuel efficiency.
Wrong Engine Timing Setting
If the engine timing is not set correctly, it can cause the combustion process to be inefficient. Moreover, improper timing can cause the fuel to ignite too early or too late.
If the fuel ignites too late, it can result in a loss of power and increased emissions.
Increased Engine Load
When the engine is under heavy loads, such as towing a heavy load or climbing steep hills, it has to work harder, generating more heat.
The increased workload makes the engine produce a higher exhaust temperature.
Damaged Valve Seat
A damaged or worn valve seat can be the source of leakage of hot combustion gasses into the exhaust system.
The hot gasses mixed with the exhaust gasses will increase the exhaust temperature.
Clogged Turbocharger
A clogged turbocharger can restrict the flow of exhaust gasses, increasing the exhaust temperatures.
Carbon buildup or foreign objects accumulation in the larger turbocharger can impede the exhaust gas flow and end up with overheating.
Blockage In The Scavenge And Exhaust Manifold
The scavenge and exhaust manifold are responsible for directing exhaust gasses out of the engine.
Over time, carbon deposits, soot, or debris can accumulate and cause blockages in these manifolds.
When the exhaust gasses cannot flow freely due to these blockages, it can increase back pressure in the system. This can make the exhaust gasses hotter, leading to higher exhaust temperatures.
Leakage Of Scavenge Air
- In diesel engine configurations, scavenge air is used to aid in cooling the exhaust gasses. If there is a leakage in the scavenge air system, the cooling effect on the exhaust gasses is affected.
- Moreover, if a scavenge air leakage occurs after the turbocharger, the air delivery to the main manifold can be restricted. As a result, there will be reduced airflow and less exhaust gas leaving the system. These problems can level up the exhaust temperature.
How To Fix High Exhaust Temperature?
The most common ways of excessive exhaust temperature are to adjust timing settings and reduce engine load.
Besides, cleaning dirty parts, and replacing damaged parts are practical solutions.
Clean Or Replaced Clogged/Damaged Parts
Clean clogged parts:
- Identify the clogged parts, such as valves, scavenge, exhaust manifolds, injectors, or filters.
- Use appropriate cleaning methods or solutions the manufacturer recommends to remove the clogs.
- Remove debris or deposits and thoroughly clean fuel injectors, valves, and filters.
Replace damaged parts:
- Recognize the damaged components, such as valve seats, fuel pumps, or injectors.
- Consult a professional mechanic or technician to determine the extent of the damage and the need for replacement.
- If necessary, replace the damaged parts with new ones following the manufacturer’s specifications.
Adjust Timing Setting
- Step 1: Connect a timing light or timing gun to your car’s battery terminals and the spark plug wire of the number one cylinder.
- Step 2: Have someone start the engine while you use the timing light to illuminate the timing numbers.
- Step 3: Direct the light onto the harmonic balancer and note the timing number indicated.
- Step 4: Adjust the timing by turning the distributor housing in the desired direction (counterclockwise to advance or to retard).
- Step 5: Adjust while the engine is idle, aligning the timing marks with the timing light.
- Step 6: Aim for a total timing between 34 and 36 degrees, ensuring it stops advancing and remains steady at around 3500 RPM.
- Step 7: Lock down the distributor by tightening the bolts and reconnecting any vacuum hoses.
Note: This process should be done by a qualified mechanic who understands the specific requirements of your engine.
Reduce Engine Load
- By avoiding hard acceleration, you allow the engine to operate more moderately, reducing the amount of fuel burned.
- Avoiding heavy towing or carrying excessive weight reduces the strain on the engine. It also prevents it from working excessively.
- Consider the load placed on the engine and operate within the recommended limits. It will optimize performance and maintain safe exhaust temperature levels.
By practicing these measures, you can help maintain the engine’s efficiency, prevent overheating, and reduce the risk of damage to engine components caused by excessive heat.
Use Pyrometer To Measure Gas Temperatures
Step 1: Install the pyrometer
The pyrometer typically consists of a sensor or probe and a display unit. Install the sensor in a suitable location where it can come in contact with the exhaust gas.
Ensure that it is securely mounted and positioned correctly for accurate readings.
Step 2: Connect the pyrometer
The sensor will have electrical wires that need to be connected to the display unit. Follow the manufacturer’s instructions for proper wiring and connection procedures.
Step 3: Adjust the pyrometer
Before taking measurements, it’s best to calibrate the pyrometer to ensure accurate readings. This involves adjusting the instrument to match a known reference temperature.
Step 4: Take measurements
Measure the exhaust gas temperatures. Position the sensor in the exhaust gas stream and allow it to stabilize for a few seconds to get an accurate reading. Read the temperature value displayed on the pyrometer’s unit.
Step 5: Monitor and analyze the readings
Continuously monitor the exhaust gas temperatures using the pyrometer. If you notice consistently high temperatures, it indicates a potential issue with the engine or exhaust system.
Consider Using An Aftermarket & Cool Air Intake
The purpose of an aftermarket air intake is to improve the airflow to the engine by allowing a higher volume of cooler air to enter.
Below are some benefits of aftermarket air intake:
- Enhanced airflow: Aftermarket air intakes often feature larger intake tubes and high-flow air filters. These pave the way for more air available for combustion.
- Reduced air temperature: Some aftermarket air intakes include heat shields or insulating materials to prevent the intake air from absorbing heat from the engine bay.
A cool air intake system draws in cooler air outside the engine bay. It does this by repositioning the intake opening to a location with direct access to cool air.
- This cooler air is denser and contains more oxygen, improving combustion and helping to regulate exhaust gas temperatures.
Cool air intakes often include an airbox or heat shield around the stock air filter, preventing warm air from being drawn in.
- High exhaust gas temperatures can be reduced by maintaining a lower intake air temperature.
Consider Installing A Water/Methanol Injection Kit
A water or methanol injection kit can help reduce exhaust gas temperatures by injecting water and methanol into the engine’s intake system. Also, it can:
- Prevent detonation and pre-ignition
- Improved combustion efficiency
- Reduce carbon deposit
- Increased intake air density
FAQs
What Are The Symptoms Of The Exhaust Temperature Is Too High?
If the exhaust temperature is too high, one common symptom is the illumination of an advisory warning light on your vehicle’s dashboard.
This light is designed to indicate high exhaust system temperature and is a precautionary measure.
Note that the exhaust temp light does not necessarily mean there is a malfunction in the engine systems.
Instead, it signals to alert you about the elevated temperature and prompts you to take appropriate action to prevent potential issues.
How To Prevent Too High Exhaust Temperature?
- Regularly monitor the high exhaust temp light on your vehicle’s dashboard: This lets you stay aware of any potential issues and take appropriate action.
- Reduce vehicle speed: If the high exhaust temperature light illuminates, reduce your vehicle’s speed. Slowing down helps lessen the load on the engine and reduces heat generation.
- Turn off accessories: To further reduce the strain on the engine, turn off half or more of the accessories that require engine power, such as the air conditioning or stereo system. It decreases the demand for the engine and lowers the overall temperature.
Conclusion
In conclusion, knowing how to fix high exhaust temperature is crucial for maintaining the performance and longevity of your vehicle.
It’s best to do regular maintenance for your engine. Checking and replacing faulty fuel valve nozzles and other damaged parts can help optimize fuel-air mixture and combustion efficiency.
Ensuring proper engine timing and adequate cooling system functionality is also essential.