An internal component of your car called a glow plug is used to help your diesel engine start. They are essential in colder climates because chilly temperatures can make it difficult for diesel engines to fully start. Diesel engines’ ability to start properly depends on the heat generated by chamber compression. An extremely cold environment without an external source of heat combined with a diesel engine prevents the diesel engine from starting. Diesel glow plugs can solve this problem!
You must be aware of how glow plugs function, how to change them, and how to ensure that your car will start in the winter. No matter where you are, it is essential to have the expertise necessary to fix these problems because roadside breakdowns can be very dangerous.
In This Article...
What does the caution light on a glow plug mean?
The Glow Plug Indicator is a typical dashboard light for diesel-powered vehicles. It illuminates while the engine’s glow plugs are still warming up, and you shouldn’t start the engine until it stops flashing. If the light continues to flash after you start the engine, an issue has been discovered and a glow plug may have worn out. A list of additional dashboard indicators for diesel-powered cars is provided below.
Note: The dashboard lights below may not exactly match the symbols and warning lights on your vehicle. There may be variations in the hues and/or patterns. For more details, consult the owner’s manual for your car.
Glow Plug Indicator
When the indicator is on, the engine’s glow plugs are warming up and it is best to wait to start the engine. If it flashes, a problem has been found, such as a glow plug that is past its prime. Install a diagnostic app
Glow plug systems: What does that mean?
Diesel engines need a little more assistance when first starting up at a chilly temperature due to their nature. When the engine temperature is too low during startup, the glow plug, which is a heating element, is turned on. To make it easier to pressurize and ignite the diesel fuel, it elevates the temperature inside the cylinders. The engine plugs need around 10 seconds to warm up before the system makes the driver wait. The computer will then permit the driver to start the engine once the appropriate temperature has been reached.
When the glow plug light is on, can you drive?
If you must continue driving when a glow plug light is flashing, drive slowly and try to limit your exposure to high speeds. An engine will frequently enter “safety mode,” and you can see a decrease in performance.
What signs or symptoms point to a failed glow plug?
Although DENSO glow plugs have a lengthy lifespan, wear and tear causes them to gradually deteriorate. How do you determine whether a set of glow plugs needs to be replaced? In this article, we examine six typical symptoms that suggest glow plugs may be defective or broken.
The dashboard’s engine warning light is frequently the first indicator that something is wrong. Vehicles with this light on should be taken as soon as possible to an authorized workshop for an accurate diagnosis and service. The engine warning light might appear due to a variety of defects; below, we list the indicators that suggest malfunctioning glow plugs.
1. Difficult start
The most typical sign of damaged glow plugs is an engine that is difficult to start. Without properly working glow plugs, the combustion chamber may not warm up to the proper temperature in cold weather to ignite the gasoline and start the engine. Glow plugs should be examined whether the battery or fuel are both in good condition.
2. An unreliable engine
Diesel engine combustion demands a high rate of compression as well as the proper timing and volume of fuel injection. This causes combustion of the diesel fuel to start. Problems with fuel quality, compression, and fuel injection can result in misfires.
Compression pressure and glow plug heat are the sources of the combustion chamber’s heat. For ignition to occur, it needs to attain a temperature of at least 450 F/232 C. The engine chamber won’t heat up to the proper temperatures if the glow plugs are defective.
3. erratic idling
The engine will become increasingly difficult to start as temperatures drop, idle erratically, and emit white smoke from the exhaust for many minutes after it eventually starts if one or more glow plugs are burned out, carbon clogged, or broken. Check the fuel injection time if the tips of every glow plug are scorched.
4. A reduction in fuel efficiency
Fuel efficiency is typically determined by temperature and fuel, not glow plug performance. Glow plugs do, however, occasionally play a part.
Diesel may be mixed with particular additives during the cold months to reduce its freezing point according on the local climate. Most likely, the energy level of the blended gasoline will be lower, and it will offer less fuel efficiency. To guarantee that all of the injected gasoline is thoroughly burned, engine operating temperatures should be regulated. Glow plugs contribute to the combustion chamber’s additional heating.
The engine’s performance will be compromised if the necessary temperature cannot be reached because of malfunctioning glow plugs, and it will have to work harder to satisfy the demands of the road. The car’s fuel economy will suffer as a result.
If the car exhibits any of the other symptoms indicated here in addition to beginning to exhibit decreased fuel efficiency, it should be taken as soon as possible to an authorized workshop for an accurate diagnosis and treatment.
5. White vapor
When there is insufficient heat to burn the fuel, white smoke frequently results. Unburned fuel particles exit the exhaust as smoke and frequently emit a strong fuel odor. White smoke from the exhaust is typical in cold weather until the engine has warmed up.
White smoke can be produced when starting an engine by damaged glow plugs or a malfunctioning glow plug control module. Low engine cranking speed, low compression, and air in the fuel system are just a few of the additional potential reasons why there is too much white smoke. After the engine has warmed up, if white smoke is still present, the engine may have faulty injectors, delayed injection timing, or a worn injection pump.
6. Dark haze
An imbalance in the air-fuel ratiotoo much fuel and not enough aircauses black smoke. This indicates that either there is an excessive amount of fuel being added or not enough oxygen is being supplied to burn the fuel. Glow plug malfunctions could interfere with the delicate diesel combustion process, which could cause the engine to exhaust black smoke. This is a red flag that something is awry, possibly with the glow plugs or other crucial combustion process elements.
Long recognized as a pioneer in OEM automobile technology, DENSO. As the leading manufacturer of automotive components today, we continuously spend in R&D to assist the top automakers in developing cars that are more responsive, efficient, and reliable.
A OEM-quality glow plug program for all manufacturers is offered by DENSO Aftermarket. DENSO Glow Plugs give customers a full range of options, from exceptional start-up performance to prolonged post-heating temperatures. All contemporary glow plug technologies, including single coil, double coil, extended post-heating, ceramic, and immediate heating, are covered by the program.
How much does a glow plug repair cost?
You should be aware that glow plug replacements are inexpensive if you put off changing your glow plugs due to the price. You may get a replacement glow plug for anywhere between $25 and $50, depending on the brand and quality.
If you have the necessary tools, changing the plugs yourself will save you money on labor. You can pay a mechanic labor fee of $90 to $200 to replace your glow plugs if you want to put convenience over quality.
The process could take up to two hours, depending on the layout of your engine and the mechanic’s level of experience. The more labor expenditures you incur, the longer the job will take.
Do defective glow plugs allow me to drive?
Your car’s engine will be challenging to start if the diesel glow plugs are bad. In order for the diesel fuel to ignite successfully after being injected into compressed air, the pressures in the cylinder must be high enough, hence a defective diesel glow plug will increase engine pressure. It becomes challenging to start your car because of this.
Engine Misfires
A misfire in the engine occurs when the fuel does not ignite properly in the cylinder. As you are aware, the diesel glow plug is crucial to the success of this ignition.
A misfire during ignition is likely if the plug is not operating properly. Although you could still be able to operate your car, its performance won’t be as good as it usually is.
Black Smoke
You may have a defective diesel glow plug if you notice black smoke coming from the exhaust pipe. Of course, there could be a number of causes for this black smoke, but a defective glow plug will undoubtedly interfere with the combustion of the diesel fuel.
It is not typical for this combustion process to produce black smoke. Take this smoke as a warning indication that something must be wrong with the diesel glow plug or another important part of the combustion process, so that you can fix it.
Engine Light On
The dashboard’s engine light or diagnostic fault code will typically illuminate when a diesel glow plug malfunctions. You should use a diagnostic scan tool to identify the issue.
The most common code displayed is P0380, which stands for Glow Plug/Heater Circuit “A Malfunction.
How frequently should glow plugs be changed?
Glow plugs should last up to 100,000 miles before gradually degrading as a result of wear and tear. The good news is that glow plugs are among the least expensive auto parts to replace and have a very long lifespan.
Why do glow plugs malfunction?
High voltages or extreme heat are the two main causes of glow plug failure. A controller that is beginning to malfunction could be the source of high voltage. Additionally, the glow plug(s) may be receiving electricity continuously if there is bad wiring or a controller issue.
Why is the glow plug light on my Audi A4 flashing?
The flashing glow light has nothing to do with the glow plugs themselves.
It is used to alert you when something is wrong with the car and needs fixing, such as a sensor that is not operating properly. In most cases, the engine light turns on and stays on after the glow light has flashed.
The fault codes must be examined in order to diagnose the real defect since there are numerous potential causes for this.
Is it simple to replace a glow plug?
Even though cars have become increasingly complicated over the years, you can still usually change your own glow plugs in most circumstances.
Make sure you have a manual torque wrench and the appropriate glow plugs for your vehicle, though, before starting the job. Champion has you covered for anything from cutting-edge Integrated Pressure Glow Plugs to Standard Glow Plugs.
Additionally, there are distinct installation procedures for each of our different glow plugs. Our specific installation techniques are listed below.
- All typical in-build glow plugs are covered in Section 1. These three types of glow plugs are Standard, Ceramic, and Instant Start System.
- The installation procedures for the Integrated Pressure Sensor Glow Plugs are covered in Section 2.
But before you get started, keep in mind the following crucial information: Glow plug replacement: Stick to the torques!