Vauxhall Insignia 2.0 Cdti Glow Plugs Replacement Cost? 97 Most Correct Answers

Which glow plug replacement service do you need?

Diagnosis of the glow plug light

If your glow plug light has come on, you need to get it checked out as soon as possible in order to get to the root of the problem. The earlier a problem is diagnosed, the easier it is usually to fix it. The glow plug light can be due to faulty crank sensors, but there are other issues that can cause the glow plug light to come on that a mechanic can diagnose for you.

Replacing the glow plug

Glow plugs have no set times when they need to be replaced. Instead, you should worry about replacing glow plugs when they don’t work. As a precaution, it’s a good idea to have your glow plugs serviced every year. To do this, the glow plug is removed and the threaded part and the cylinder head lubricated with special ceramic grease are cleaned.

Defective or seized glow plugs

When it comes time to replace glow plugs, sometimes they are broken or seized making them difficult to remove. This can happen when the glow plugs are seized from corrosion, rust, or carbon buildup.

The top warning signs that your glow plug needs to be checked

Here are the warning signs that your glow plugs may need repair:

The glow plug warning light comes on on the dashboard.

If your car’s engine is difficult to start, this is a common symptom of bad glow plugs.

Diesel engine misfires can be caused by problems with fuel quality, compression, and fuel injection.

Decreased fuel efficiency.

If you notice white smoke when you start your engine, this could be a sign of bad glow plugs

Your engine can produce black smoke from the tailpipe because damaged glow plugs affect the diesel combustion process.

Is a glow plug change necessary?

Yes – If you notice any telltale signs that the glow plugs are bad, it’s definitely time to book your car with a workshop technician. The good news is that glow plugs are extremely durable, often running up to 100,000 miles. Over time they deteriorate due to wear and tear, but when they do they are very inexpensive auto parts that need to be replaced.

Find glow plug replacement workshops near you

Looking for top glow plug replacement specialists in your area?

95 shares share

Pen

tweet

(Updated July 28, 2022)

In order to successfully start a diesel engine, it needs a special heating component called a diesel glow plug. A diesel engine cannot start and run properly without the heat generated by this spark plug.

If you typically drive your diesel powered vehicle in colder environments, your engine relies on the diesel glow plug to generate the heat it needs to operate. The cold temperatures would otherwise make it impossible to start the vehicle.

In addition, the cylinder block and cylinder head also absorb much of this heat. Since the diesel glow plug is positioned inside the combustion chamber, it will transfer this heat to the engine.

How a glow plug works

Diesel glow plugs always heat up the engine’s cylinder before the fuel is ignited. This makes it easier for the fuel to ignite in the cylinder.

Don’t confuse glow plugs with spark plugs, they are two different things. Spark plugs in a regular gasoline engine are responsible for creating an electrical spark that ignites the air-fuel mixture. The glow plugs only warm up the cylinder to make it easier for the fuel to self-ignite.

A glow plug has an electrode that generates heat when activated. This makes the candle glow, which is why it is called that. This is similar to the glow of an incandescent lamp after it has also warmed up. This glow effect heats the cylinder and allows the diesel fuel to ignite successfully.

Here’s a good simple demonstration of how a diesel glow plug works:

Top 4 bad diesel glow plug symptoms

You now know that the diesel glow plug is a necessity for a diesel engine to function properly. So, if for some reason the diesel glow plug becomes damaged or defective, the symptoms are easy to spot. In fact, this will change the functionality of the entire car.

Here are four of the most common symptoms of a bad diesel glow plug.

See also: Bad Spark Plug Symptoms

1) Difficulty starting the engine

Bad diesel glow plugs make it difficult to start your car engine. Since the pressure in the cylinder is mainly responsible for igniting the diesel fuel after it has been injected into compressed air, a bad diesel glow plug puts more pressure on the engine for this ignition to be successful. Therefore, starting your vehicle becomes difficult.

2) Engine misfires

If the fuel in the cylinder does not ignite properly, it will cause the engine to misfire. As you know, the diesel glow plug plays a crucial role in the success of this ignition.

If the spark plug is not working properly, there is likely to be a misfire during ignition. You may still be able to drive your vehicle, but you will experience a decrease in normal performance.

3) Black smoke

If you see black smoke coming out of the exhaust pipe, this could be an indication that you have a faulty diesel glow plug. Of course, there can be several reasons for this black smoke, but a bad glow plug will certainly dampen the diesel combustion that is taking place.

Black smoke is not a normal part of this combustion process. So take this smoke as a warning sign that something is wrong with either the diesel glow plug or another important component of the combustion process.

4) Engine light on

Usually when the diesel glow plug malfunctions, the diagnostic trouble code or engine light illuminates on the dash. To determine the problem, you should use a diagnostic scan tool.

Commonly, the code displayed is P0380: Defined as a malfunction of the glow plug/heater circuit ‘A’.

Glow Plug Replacement Cost

Looking for spare parts? Parts Geek for the best prices and selection. We recommend for the best prices and selection.

The typical replacement cost for a diesel glow plug is between $95 and $210. The cost of a single glow plug ranges from $15-$50, while labor costs are around $80-$160.

Remember that each cylinder has its own glow plug. So if you have a full-size truck with a V8 engine, you might want to replace all eight glow plugs, even if only one is known to be bad. Labor costs won’t be too much higher regardless of whether one glow plug went out or many.

It is similar to replacing spark plugs. Sure, you can only replace the bad one, but there’s a good chance another one or all the others will soon fail anyway.

The exact cost will depend on the make and model of your diesel vehicle and whether you are taking it to a dealer or auto repair shop.

In general, the part itself isn’t too expensive, but compared to gasoline engines, even the best spark plug is likely to cost more than a cheap glow plug. Finding a cheap mechanic with a low hourly rate will reduce your costs even further.

Installation steps for standard glow plugs and integrated pressure sensor glow plugs

While cars have gotten more complex over the years, changing your vehicle’s glow plugs is still, in most cases, a job you can do yourself.

However, before you get to work, make sure you have a manual torque wrench and the correct glow plugs for your vehicle. From advanced integrated pressure glow plugs to standard glow plugs, Champion® has you covered.

And with our various glow plugs, there are different installation steps. Below are our specific installation procedures.

Section 1 covers all standard glow plugs. These are the standard, ceramic and instant start system glow plugs.

Section 2 covers the installation steps for the Glow Plugs with Integrated Pressure Sensor.

Now you know exactly where the journey is going.

But before you get started, here are some important tips that you should observe: When changing glow plugs: Observe the torques!

Chapter 1: Glow Plugs Instructions (Standard, Ceramic and Instant Start System)

Removing the old glow plugs

You’ve left the bonnet behind, you’ve made it further and you’ve made your way to the glow plug. Now it’s time to manage the torque. Here is our step-by-step guide on how to remove the plug:

First of all: Only remove and install glow plugs with a manual torque wrench.

What do I have to do when the tightening torque is reached?

Do not turn any further – otherwise the glow plug can break off. Instead, follow the 3-point program “slightly loosen – heat – unscrew”:

1. Slightly loosen: apply synthetic oil generously to the glow plug thread and leave it on overnight or longer if possible.

2. Warm up: Allow the engine to warm up or supply the functional glow plugs with power for 4-5 minutes via a separate cable (only possible for glow plugs with an operating voltage of 11 – 12 V) – the glow plug gets hot and starts to burn.

3. Unscrew: Then try again to unscrew the glow plug and carefully loosen the glow plug from the cylinder head with a suitable tool. (Do not exceed the maximum loosening torque. Always stop before reaching the tightening torque, if necessary try again by heating.)

After removing the old glow plugs, always clean the thread, the cone seat and the glow plug channel in the cylinder head with suitable tools.

Installation of the new glow plugs

tightening torque

When screwing in new glow plugs, the tightening torque specified by the vehicle manufacturer must be observed and carried out with the appropriate reamer.

Note:

In the case of glow plugs with a screw connection, the tightening torque of the connection nut must also be observed. Refer to the information on the packaging of your Champion® glow plug for this product-specific information.

Especially after burning in (coking) between the glow rod and the cylinder head, the cylinder head bore is often contaminated by fire residues or dirt particles. Such carbon deposits can be easily and safely removed from cylinder heads with a 10 mm thread.

Section 2: Instructions for glow plugs with integrated pressure sensor

Removing the old glow plugs from the integrated pressure sensor

When changing plugs, special care is required to avoid damage to the highly sensitive sensor and to ensure full functionality:

Beware:

A fall from a height of just 2 cm can damage the integrated pressure sensor.

Only unplug the connector by hand to avoid the risk of damaging the connector.

Installation and removal only with appropriate special tools. Press the tool onto the glow plug with integrated pressure sensor so that the hex head of the glow plug is completely covered; Observe the torque.

Only remove the protective cap after installing the glow plug.

The correct way to remove:

1. Remove the engine cover and other components that impede access to the glow plugs. 2. Manually disconnect the electrical connector on each glow plug. Important: Detach the connector manually and do not use any tools such as pliers or similar.

3. To ensure that no foreign objects enter the combustion chambers, clean the area around the relevant glow plug. 4. If the fuel system has been opened, also ensure cleanliness and, if possible, seal the cables with a cap. 5. It is important to use only the appropriate socket when loosening the integrated pressure sensor glow plug; This will prevent damage to the terminal block. 6. Important: Full coverage of the connector hex. Please use a torque wrench and observe the permissible breaking torque. 7. Remove the glow plug.

More tips for installation that protects the glow plugs

8. Coat the thread and shaft of the new plug with glow plug assembly grease before installing it to prevent it from caking later.

9. First clean the glow plug channel and the thread in the cylinder head from oil and combustion residues. Then screw in the glow plug by hand. Important: Make sure that no dirt gets into the combustion chamber. 10. Then tighten with a torque wrench (observe the assembly torque!) with a suitable socket. Important: Complete coverage of the hex head of the glow plug with integrated pressure sensor. Now (only now!) remove the protective cap from the connector to prevent damage to the connector and mating connector.

11. Push the wire harness until it snaps onto the integrated pressure sensor glow plug. 12. Install the engine cover and any other parts previously removed.

13. Finally, check the memory of the engine control unit for fault code entries and erase them.

The content of this article is for informational purposes only and should not be used in lieu of professional advice from a certified technician. We encourage you to contact a certified technician if you have specific questions or concerns about any of the topics discussed here.

gauge and you get no reading, that’s an open glow plug; Burned out would show a solid short.”

…”

“Helped a friend with glow plug issues. Learned how they worked, change, test. Good stuff. Note: when testing with

How do you know when it’s time to replace your glow plugs?

Is it difficult to start your diesel pickup truck when it’s cold outside? If so, it may be time to replace your glow plugs.

What are glow plugs?

Glow plugs are a heating element that is part of the ignition process in diesel engines. Glow plugs are located in each cylinder of the engines and use battery voltage to generate heat. It is this heat that helps ignite the diesel fuel during the starting process. If your diesel engine lacks this extra heat, it can cause starting problems. *Hard starting is when the engine cranks but does not start.

Diesel engines cannot start “cold”. You must give the glow plugs some time to warm up before fully turning on the ignition system. They usually have a dash light that shows when it’s safe to turn the ignition fully on. Starting the engine while the glow plugs are warming up is a BIG no-no. Especially in the winter months when it is particularly cold.

How long do glow plugs last?

The average life of a glow plug on a diesel engine is approximately 100,000 miles. So it’s not something you have to worry about all that often. However, they can fail before then, especially if you frequently have hard starts or use a lower quality glow plug than recommended in your pickup.

How do you know when it’s time to replace the glow plugs?

Often the glow plugs on a diesel engine are overlooked until they no longer work. As a diesel pickup truck owner, it is important that you understand the signs of blown glow plugs and act quickly to replace them. The longer you wait before replacing defective glow plugs, the more damage you have to accept.

If a glow plug fails, your pickup truck’s combustion chamber will not receive the heat it needs to ignite. On warmer days you may be able to reach ignition after several attempts to start. However, in colder winter temperatures, it is very unlikely that your engine will even fire if the glow plugs are bad.

There are other signs that you have glow plug issues on your hands aside from your pickup truck not starting when cold. Knowing what these signs are and acting accordingly can help ensure you are not stranded.

Here are six signs it’s time to replace your glow plugs:

Decreased fuel efficiency

Difficult acceleration

Engine misfire

Difficult starting or no starting at all, especially in cold weather

power loss

The vehicle emits more smoke than normal

Driving your pickup in these conditions can be unsafe and potentially cause further, more expensive damage.

When the time comes, it is best to have the glow plugs replaced by a professional as it is a laborious process. We can help. Gem State Diesel & Turbo Repair is well known in the Boise area for diesel pickup truck repair and service. Make an appointment online or call us at 0208-288-5555.

When is a dead battery not a dead battery? If there is a problem with glow plugs. OK, that’s oversimplifying a bit, but a lot of times people will collapse on what they think is a battery problem, only to find out the glow plugs are to blame.

The reason for this is that diesel engines use these heaters to help them start. In warmer weather they are not as necessary. However, when it gets cold, glow plugs are indispensable. As a result, in November 2017, the number of Green Flag engagements for glow plug issues increased by 112 percent. Read on to find out what the problem is and how to diagnose it.

What are glow plugs?

Diesel engines rely on the heat of compression rather than spark plugs to ignite the fuel in the cylinder. But at low temperatures, the cold engine block absorbs any compression heat, making starting difficult. The glow plug provides the answer and ensures that it is an essential part of the modern diesel engine.

Although you’ll probably never see one in action since they’re buried deep inside the engine, glow plugs look like a pen. And their tip lights up, much like a car’s cigarette lighter, hence the name. This glowing end provides extra heat in each cylinder, making it easier to ignite the fuel and start the engine. As soon as the engine is running, the glow plugs go back to idle.

How do you know glow plugs work?

When you turn on the ignition of the diesel vehicle, the glow plug icon (below) on the dashboard will illuminate. After less than a handful of seconds, this will go out, indicating that the glow plugs have done their job, the cylinders have heated up and the engine is ready to start. On more modern diesel cars, which have a start button instead of a key, the car’s computer knows to delay starting until the glow plugs have done their thing.

What happens when glow plugs fail?

You know your glow plugs are worn out because the orange light on the dash stays on longer before going out. And the car might have trouble starting. Eventually, in colder weather, the symptoms may seem like a dead battery. This is because if you try to start the engine you will crank the engine in vain but the battery will be drained. In the end, the battery will cry enough. But that’s more the effect of the bad glow plugs making it difficult to start, rather than the cause of the problem.

Since most cars have four-cylinder engines, that means four glow plugs. If a glow plug fails, the engine may still start, but may be rough at first. This is because without a working glow plug, the cylinder needs some time to warm up and function properly. When that happens, it tells you that the glow plugs need to be replaced.

How long do glow plugs last?

That’s a tough question to answer, but at least we’re looking at tens of thousands of miles. The glow plug is only used during the starting phase. This means that those in a car that drives a lot of short trips get more use and have a shorter lifespan in terms of miles than those in cars that do a lot of mileage between starts.

Scott Wilson is the vehicle and customer data insight manager for Green Flag

Share this: Twitter

Facebook

How to change your glow plugs

Powered by the battery, glow plugs heat fuel to prepare for combustion. They regulate diesel engine temperatures for healthy vehicle performance.

While gasoline cars use spark plugs to ignite fuel, glow plugs rely on compression rates to raise air temperature to the burn point in diesel vehicles.

Diesel engines require one glow plug per cylinder, which means they use up to ten plugs.

Glow plugs wear out with age, and cold weather will cause them to deteriorate faster than warm weather. Because of this, it is important that you regularly service your glow plugs and replace them when they are damaged.

Servicing your glow plugs yourself will save you the time and expense required to have your car serviced at a workshop.

rajivanoj FORBIDDEN

Joined Date: March 2007 Location: Coimbatore Contributions: 398 Thanked: 50 times

Check out my garage

Should I replace all four glow plugs? My Lancer diesel had a slight starting problem in the morning, it took about 2 revs to start, then I checked the battery, it’s ok if not the best.

Then I asked the mechanic to check the glow plugs after reading on a forum that to check glow plugs it has to be 0.5 ohms (standard) – 1 ohm maximum. I checked with my meter that I had for my factory purposes but two plugs gave 0.02 ohms and one gave 0.33 ohms the other gave 0.8 ohms.

So I concluded two were gone and to be sure I took it to an electrician after he verified two were gone.

My question is whether to replace all plugs or just replace faulty ones. Will this lead to future problems like premature failure of other plugs when half-value plugs are used with new ones?

I inquired about the price, the HKT brand (imported) is 250-275 rupees each.

According to this Bosch page, their glow plug was developed in the early 1920’s.

But before that, the diesel engine had been around for at least 20 years; For example, the French used it in a submarine in 1904.

Given that diesel technology relies on auto-ignition, how did they get the engine up to temperature without a glow plug?

What are the most common problems with diesel glow plugs?

There can be several diesel glow plug problems. Usually, glow plug failure is due to excessive heat or high voltages reaching the plug. High voltage can be caused by a controller starting to go bad. Also, if there is faulty wiring or a problem with the controller, the glow plug(s) may be getting power all the time. Since the plugs are not designed to be on all the time, they will burn out prematurely. In addition, excessive heat conditions can be caused by engine timing or fuel leaking from the injectors. Of course, running gasoline in the engine will damage the glow plug tip due to heat build-up in the prechamber.

See How to Replace the Diesel Glow Plugs for more information

Installation steps for standard glow plugs and integrated pressure sensor glow plugs

While cars have gotten more complex over the years, changing your vehicle’s glow plugs is still, in most cases, a job you can do yourself.

However, before you get to work, make sure you have a manual torque wrench and the correct glow plugs for your vehicle. From advanced integrated pressure glow plugs to standard glow plugs, Champion® has you covered.

And with our various glow plugs, there are different installation steps. Below are our specific installation procedures.

Section 1 covers all standard glow plugs. These are the standard, ceramic and instant start system glow plugs.

Section 2 covers the installation steps for the Glow Plugs with Integrated Pressure Sensor.

Now you know exactly where the journey is going.

But before you get started, here are some important tips that you should observe: When changing glow plugs: Observe the torques!

Chapter 1: Glow Plugs Instructions (Standard, Ceramic and Instant Start System)

Removing the old glow plugs

You’ve left the bonnet behind, you’ve made it further and you’ve made your way to the glow plug. Now it’s time to manage the torque. Here is our step-by-step guide on how to remove the plug:

First of all: Only remove and install glow plugs with a manual torque wrench.

What do I have to do when the tightening torque is reached?

Do not turn any further – otherwise the glow plug can break off. Instead, follow the 3-point program “slightly loosen – heat – unscrew”:

1. Slightly loosen: apply synthetic oil generously to the glow plug thread and leave it on overnight or longer if possible.

2. Warm up: Allow the engine to warm up or supply the functional glow plugs with power for 4-5 minutes via a separate cable (only possible for glow plugs with an operating voltage of 11 – 12 V) – the glow plug gets hot and starts to burn.

3. Unscrew: Then try again to unscrew the glow plug and carefully loosen the glow plug from the cylinder head with a suitable tool. (Do not exceed the maximum loosening torque. Always stop before reaching the tightening torque, if necessary try again by heating.)

After removing the old glow plugs, always clean the thread, the cone seat and the glow plug channel in the cylinder head with suitable tools.

Installation of the new glow plugs

tightening torque

When screwing in new glow plugs, the tightening torque specified by the vehicle manufacturer must be observed and carried out with the appropriate reamer.

Note:

In the case of glow plugs with a screw connection, the tightening torque of the connection nut must also be observed. Refer to the information on the packaging of your Champion® glow plug for this product-specific information.

Especially after burning in (coking) between the glow rod and the cylinder head, the cylinder head bore is often contaminated by fire residues or dirt particles. Such carbon deposits can be easily and safely removed from cylinder heads with a 10 mm thread.

Section 2: Instructions for glow plugs with integrated pressure sensor

Removing the old glow plugs from the integrated pressure sensor

When changing plugs, special care is required to avoid damage to the highly sensitive sensor and to ensure full functionality:

Beware:

A fall from a height of just 2 cm can damage the integrated pressure sensor.

Only unplug the connector by hand to avoid the risk of damaging the connector.

Installation and removal only with appropriate special tools. Press the tool onto the glow plug with integrated pressure sensor so that the hex head of the glow plug is completely covered; Observe the torque.

Only remove the protective cap after installing the glow plug.

The correct way to remove:

1. Remove the engine cover and other components that impede access to the glow plugs. 2. Manually disconnect the electrical connector on each glow plug. Important: Detach the connector manually and do not use any tools such as pliers or similar.

3. To ensure that no foreign objects enter the combustion chambers, clean the area around the relevant glow plug. 4. If the fuel system has been opened, also ensure cleanliness and, if possible, seal the cables with a cap. 5. It is important to use only the appropriate socket when loosening the integrated pressure sensor glow plug; This will prevent damage to the terminal block. 6. Important: Full coverage of the connector hex. Please use a torque wrench and observe the permissible breaking torque. 7. Remove the glow plug.

More tips for installation that protects the glow plugs

8. Coat the thread and shaft of the new plug with glow plug assembly grease before installing it to prevent it from caking later.

9. First clean the glow plug channel and the thread in the cylinder head from oil and combustion residues. Then screw in the glow plug by hand. Important: Make sure that no dirt gets into the combustion chamber. 10. Then tighten with a torque wrench (observe the assembly torque!) with a suitable socket. Important: Complete coverage of the hex head of the glow plug with integrated pressure sensor. Now (only now!) remove the protective cap from the connector to prevent damage to the connector and mating connector.

11. Push the wire harness until it snaps onto the integrated pressure sensor glow plug. 12. Install the engine cover and any other parts previously removed.

13. Finally, check the memory of the engine control unit for fault code entries and erase them.

The content of this article is for informational purposes only and should not be used in lieu of professional advice from a certified technician. We encourage you to contact a certified technician if you have specific questions or concerns about any of the topics discussed here.

gauge and you get no reading, that’s an open glow plug; Burned out would show a solid short.”

…”

“Helped a friend with glow plug issues. Learned how they worked, change, test. Good stuff. Note: when testing with

Glow plugs are used in diesel engines to heat the fuel in preparation for the combustion chamber when the engine is cold. They operate on any 12 volts available from the battery and are located on top of the cylinders. They are used frequently, and the duration of their use is determined by the weather conditions where you live. Cars in colder areas are likely to need new glow plugs much more frequently, while glow plugs in warmer areas can last 100,000 miles. With continuous use and extreme temperature fluctuations, glow plugs are a hard-working part. Rough starting or misfiring at cranking, smoking at cranking, and difficulty starting in cold conditions are basic signs of a bad glow plug. They tend to be relatively inexpensive and easy to replace with the right tools.

Part 1 of 1: Replace your glow plugs

Materials needed

Deep socket set and ratchet

Tongs

replacement glow plugs

socks set

Rocker Cover Gaskets (if present and to be replaced)

Step 1: Disconnect the battery cable. Locate and disconnect the negative battery black cable. Whenever working on any electrical system in your vehicle, always disconnect the battery cable first. Glow plugs are routed so that the full 12 volts are available from the battery.

Note: When replacing parts such as glow plugs, some digging is often required to get to the part. This varies greatly by make, model and year. Track everything you remove or set aside when accessing your vehicle’s glow plugs. It’s good practice to wrap and label your screws and bolts.

Step 2: Remove the valve cover (if applicable). If the glow plugs are under the valve covers, you will need to remove them first. If not, continue to step 3. To remove the valve cover, loosen all of the retaining screws around the perimeter of the cover. Pay attention to the valve cover gaskets between the engine and the cover.

Note: This is an excellent time to replace the rocker cover gaskets on your vehicle.

Step 3: Locate the glow plugs. The glow plugs are screwed into the cylinder head. Look for the tip that is sticking out and the wire that provides your 12 volt power supply.

Step 4: Disconnect power to the glow plugs. There is a nut, bolt, plastic connector or other type of connecting device at the top to quickly remove the wire from the glow plug. Release the clamp and set the wires aside. Newer models have a connection similar to spark plugs. These can be pulled straight off (pliers will help, but be careful not to break the clamp).

Step 5: Remove the glow plug. Use a socket and ratchet to remove the plug. Place the ratchet over the plug and turn to the left (counterclockwise). This may require a deep socket. These should come out mostly clean. You can tell how damaged it is by the length and shape of the plug (see image below).

Note: Glow plugs can fail in their compartment. If you are removing a bad spark plug, make sure you remove all the bad parts from the engine.

Step 6: Prepare to install the new glow plug. Now it’s time to take some precautions and possibly upgrade the parts associated with the glow plugs. Clean the area around the glow plug hole opening. If the supply terminal is dirty, use a wire brush or suitable tool to clean it for a solid connection.

Step 7: Install the new glow plugs. Hand-tighten them into position. Use your socket and ratchet to hold it firmly in place. Be careful not to over tighten. This will damage the connector, prevent proper operation, or possibly damage the connector in its place.

Step 8: Connect the power adapter. Reconnect the wires that power the glow plugs. These should be screwed in or snapped into place exactly as you removed them in step 4.

Step 9: Replace the valve covers. Replace the valve covers or anything that was removed when accessing the glow plugs. If you removed the valve covers, it is now time to replace the gasket between the cover and the valve block. Reinstall all the screws removed with the valve box after replacing the gasket. Hand tighten them and then use your ratchet to tighten them.

Note: Some manufacturers require the valve screws to be tightened to a specific pressure. Contact your vehicle manufacturer for this information when it comes to removing the valve cover.

Step 10: Connect the negative battery cable. Reconnect the negative battery cable to the battery. This will restore power to the vehicle and the glow plugs can be tested with a scan tool or multimeter if desired.

Glow plugs are required to bring freezing conditions in the engine up to viable operating temperatures quickly. You then need to switch off and cool down just as quickly. They are worked hard considering they are subjected to drastic temperature changes with each use. It is common for them or the other parts associated with them to need to be replaced. If you don’t want to replace your glow plugs yourself, trust a Vermin Club certified mechanic for fast, friendly service at your home or office.

Glow plugs have a long service life, but they gradually wear out with wear. So how do you know if a set of glow plugs needs replacing? In this article, we look at six common signs that glow plugs might be bad or damaged.

Something is wrong: the check engine light

The check engine light on the dashboard is often the first indication that something is wrong. Vehicles with this light should be taken to an authorized workshop for proper diagnosis and maintenance as soon as possible. A number of faults can cause the check engine light to come on – below we outline the indicators that indicate defective glow plugs.

Hard start

A hard-to-start engine is the most common indicator of damaged glow plugs. In the cold and without properly functioning glow plugs, the combustion chamber may not reach the correct temperature to ignite the fuel and start the engine. If there are no fuel or battery problems, the glow plugs should be checked.

Engine misfire

The combustion process in diesel engines requires a high compression rate, fuel injection at the right time and in the right amount. This ignites the diesel fuel, resulting in combustion. Misfire can be caused by fuel quality, compression, and fuel injection problems.

Rough idle

If one or more glow plugs are blown, fouled with carbon or damaged, the engine will become increasingly difficult to start as the temperature drops and will idle erratically for a few minutes after it has finally started, producing white smoke from the exhaust. When all the glow plugs are burned at their tips, check the fuel injection timing.

Decreased fuel efficiency

Temperature and fuel usually determine fuel efficiency, not glow plug performance. In some cases, however, glow plugs play a role.

Depending on the local climate, diesel can be mixed with certain additives during the cold months to lower its freezing point. The blended fuel will most likely have lower energy content and provide reduced fuel efficiency. Engine operating temperatures should be adjusted to ensure that all injected fuel is fully combusted. Glow plugs provide additional heat in the combustion chamber.

If the required temperature is not reached due to defective glow plugs, the engine’s performance will be weakened and it will have to make extra efforts to meet the demands of the road. The fuel efficiency of the vehicle is negatively affected.

If the vehicle has exhibited other symptoms listed here and is also beginning to show reduced fuel efficiency, it should be taken to an authorized workshop for proper diagnosis and maintenance as soon as possible.

White smoke

White smoke usually occurs when there is not enough heat to burn the fuel. The unburned fuel particles exit the tailpipe as smoke, typically producing a rich fuel odor. It is not uncommon to see white smoke coming out of the exhaust in cold weather until the engine has warmed up.

Damaged glow plugs or a defective glow plug control unit can produce white smoke when the engine is started. There are also many other possible causes of excess white smoke, including low engine speed, low compression, and air in the fuel system. If white smoke is still visible after the engine has warmed up, the engine may have one or more bad injectors, delayed injection timing, or a worn injection pump.

Black smoke

Black smoke is caused by an air/fuel ratio imbalance – too much fuel and not enough air. This means that either too much fuel is being added to the mixture or not enough oxygen is being added to burn the fuel. Defective glow plugs can disrupt the diesel’s delicate combustion process, which in turn can cause the engine to emit black smoke from the tailpipe. This is a warning sign that something is wrong with either the glow plugs or other important components of the combustion process.

For more information call Thomas Group on: 01233 642816

© Denso