Information - Spark plug

Spark plugs play an important role in ensuring the smooth operation of the engine of any car. Spark plug is a device necessary to ignite the fuel-air mixture in internal combustion engines of the vehicles. The mixture is ignited immediately when the spark passes between the spark plug electrodes. Hence, there appeared another name of the part - a spark plug. The spark plug operates in all types of ignition systems: electronic, contact and contactless. The spark plug has the following construction: contact bar, centre electrode, insulator and housing.

If you equip your vehicle with quality spark plugs, you will immediately notice a number of advantages. First, there is a reduction of load on the engine and its work is improved both when idle and when the engine is cold. Second, the torque throughout the rev range is increased and dynamics and flexibility of the engine are greatly improved. And thirdly, the fuel consumption and emissions of pollutants are reduced.

The main cause of early failure of the plugs is their contamination with products of incomplete combustion or spark gap increase because of wear of the electrodes. At the same time a decisive influence on the performance of sparks has the technical condition of the vehicle engine. You can tell a lot about the engine when examining the appearance of a plug. Inspection of the plug should be carried out after a long operation of the engine. An ideal variant is to inspect the plugs immediately after a long- distance trips by suburban highway.

How to reduce consumption of gasoline and to increase in engine power? How to ensure a stable safe operation of spark plugs in different operating conditions? Purchase spark plugs in our online shop at the best manufacturer prices. And we will make sure the delivery to be carried out in short terms. In addition to spark plugs, in our online store you can also buy ignition coil, ignition module or control unit.

What is necessary to know about spark plugs replacement: lifetime limits, common defects and their signs, tips and recommendations

Lifetime of the spark plugs depends on their type and quality of fuel used and car operation conditions. Manufacturers recommend to perform replacement of the nickel plugs every 20 000 – 30 000 operational kilometers. Platinum spark plugs serve longer, for about 60 000 – 70 000 kilometers. Lifetime limit of the iridium spark plugs reaches 80 000 – 100 000 kilometers of mileage. If the components break down earlier, they should be immediately replaced.

Common defects of the spark plugs are: formation of carbon, oil or fuel deposits on the electrodes, wear, melting or corrosion of the electrodes, thermal damages and wear of the plug socket, cracking or soiling of the isolator.

Necessity of spark plugs diagnostics can be detected by such signs as worsened car dynamics, troubled start, lowered power, unstable operation of the engine at idling. Also fuel consumption increases, jerks and excessive noise during engine start appear.

Components defects can be diagnosed during visual inspection. The blackened spark plugs may indicate heat rating too high for this engine, defects of high-voltage wiring or the isolator. White deposits on the spark plug, on the opposite, may indicate too low heat rating. Reddish tinge on the components also indicates necessity of their replacement. Operative components should have no patina nor oil or fuel stains.

In order to replace the spark plugs kit, you need to contact a service station. This is determined by labour intensity of the procedure, necessity of working with high-voltage wires and usage of special tools. It is very important to prevent ingress of dust and litter to plugs mounting seats, and observe tightening torque of the plug, during work performance.

Our customers ask

Which spark plugs are better to select for your car?

  • In order to select the best spark plugs for your car, focus on brand reputation and popularity. Give preference to such brands as Denso, NGK, Febi, Bilstein, Champion, Vemo, Bosch. The spark plugs of these manufacturers are notable for high quality, reliability, durability and are able to assure faultless operation of your car engine.
  • It is also important to select parts in accordance with vehicle technical requirements and its operation conditions. Iridium or platinum spark plugs will be excellent for the injector, as they characterized by continuous lifetime and efficiency. Special plugs with an additional protective coating, less plug gap, and which are designated for higher temperatures are better for cars, operating on LPG.

What is the spark plug gap for LPG engine? How do they differ from plugs for petrol engine?

The main difference between spark plugs for petrol and LPG engines lies in a size of gap, heat range and electrode thickness. Fuel mixture of the engines operating on LPG, combusts at higher temperature, that is why for their proper operation it is recommended to use the spark plugs with higher heat range, than for the injection engines. In order to lower the risk of misfires, these plugs have smaller spark gap, and the central electrode is thinner. In most cases, precious metals are used for their production, as platinum or iridium spark plugs withstand higher loads. During components selection, necessarily specify which spark plugs are used in your car, because some parameters, for example, dimensions or gap, should be precisely equal to technical requirements of the vehicle.

How to check spark plugs at home?

  • In order to check the spark plugs on your own, at first, you need to make sure that the high-voltage wires have no breakage using a multimeter. To do so, switch the device to “ohmmeter” mode, attach rods to both sides of the wire and measure resistance. Compare obtained value with ones, noted on wires insulation. Usually, faultless components have 3,5–10 kOhm resistance. If there is no breakage in the wire, you can continue to check operability of the spark plugs.
  • Checking of spark plugs operable condition at home lies in their visual diagnostics. To do so you need to unscrew them from the mounting spots and examine them: fouling on the surface, deformation and mechanical damages may point out defectiveness of the parts. If during visual inspection no visible damages were found, but the spark plugs do not produce spark, more thorough diagnostics of the whole ignition system is required, including the coil, igniter and other components.

When is it necessary to replace spark plugs?

The copper-nickel spark plugs should be replaced about after 20 000 – 30 000 kilometers of mileage, iridium and platinum – after 60 000 – 120 000 km. But if poor-quality fuel is used for the car, the crankcase ventilation system or fuel supply system are inoperable, the components may break down earlier. As a rule, you can understand that time for replacement or cleaning of the spark plugs has come by increasing of fuel consumption, lowering of engine power or its troubled start, and by car jerks during driving. If you noticed even one of these signs, it is necessary to perform diagnostics of the spark plugs as soon as possible.

Spark plug at low cost: Top Spares

Spark Plug 0,9mm, 14mm, 3mm (RIDEX, 686S0002) -22%
Spark Plug | RIDEX 686S0002 Article №: 686S0002
RIDEX Spark Plug 686S0002
£ 1,99
£ 1,55
incl. 20% VAT, Shipping
Over 100 items in stock
  • Outer thread [mm] 14
  • Thread Length [mm] 19
  • Spark Position [mm] 3
  • Electrode Gap [mm] 0,9
  • Spanner Size 16
  • Thread Pitch [mm] 1,25
  • Tightening Torque [Nm] 28
  • Number of Poles 1
  • Tightening angle [degrees] 90
  • Condition  New
Details
Spark Plug 0,8mm, 14mm, 3mm (RIDEX, 686S0003) -22%
Spark Plug | RIDEX 686S0003 Article №: 686S0003
RIDEX Spark Plug 686S0003
£ 1,99
£ 1,55
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Over 100 items in stock
  • Outer thread [mm] 14
  • Thread Length [mm] 19
  • Spark Position [mm] 3
  • Electrode Gap [mm] 0,8
  • Spanner Size 16
  • Thread Pitch [mm] 1,25
  • Tightening Torque [Nm] 28
  • Number of Poles 1
  • Tightening angle [degrees] 90
  • Condition  New
Details
Spark Plug 0,8mm, 14mm, 7mm (BOSCH, 0 242 240 665) -22%
Spark Plug | BOSCH 0 242 240 665 Article №: 0 242 240 665
BOSCH Spark Plug 0 242 240 665
£ 11,49
£ 8,96
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Over 100 items in stock
  • Outer thread [mm] 14
  • Product line Iridium
  • Thread Length [mm] 19
  • Spark Position [mm] 7
  • Electrode Gap [mm] 0,8
  • Spanner Size 16
  • Thread Pitch [mm] 1,25
  • Tightening Torque [Nm] 28
  • Number of Poles 1
  • Tightening angle [degrees] 90
  • Condition  New
Details
Spark Plug 1mm, 14mm, 4mm, Super 4 (BOSCH, 0 242 232 502) -22%
Spark Plug | BOSCH 0 242 232 502 Article №: 0 242 232 502
BOSCH Spark Plug 0 242 232 502
£ 4,99
£ 3,89
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Over 100 items in stock
  • Outer thread [mm] 14
  • Supplementary Info Super 4
  • Thread Length [mm] 19
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  • Spanner Size 16
  • Thread Pitch [mm] 1,25
  • Tightening Torque [Nm] 28
  • Number of Poles 4
  • Tightening angle [degrees] 90
  • Condition  New
Details
Spark Plug for vehicles without catalytic convertor CNG/LPG Motronic Single Point Injection (SPI) France (DENSO, IK20TT) -22%
Spark Plug | DENSO IK20TT Article №: IK20TT
DENSO Spark Plug IK20TT
£ 10,99
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Over 100 items in stock
  • Product line Iridium TT
  • Spanner Size 16
  • Spark Plug 1 - Earthed Electrode
  • Thread Size 1 19
  • Tightening Torque [Nm] 22
  • Diameter [mm] 14
  • Weight [g] 43
  • Condition  New
Details
Spark Plug 0,8mm, 14mm, 3mm (STARK, SKSP-1990002) -22%
Spark Plug | STARK SKSP-1990002 Article №: SKSP-1990002
STARK Spark Plug SKSP-1990002
£ 1,99
£ 1,55
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Over 100 items in stock
  • Outer thread [mm] 14
  • Thread Length [mm] 19
  • Spark Position [mm] 3
  • Electrode Gap [mm] 0,8
  • Spanner Size 16
  • Thread Pitch [mm] 1,25
  • Tightening Torque [Nm] 28
  • Number of Poles 1
  • Tightening angle [degrees] 90
  • Condition  New
Details
Spark Plug 0,9mm, ULTRA TITAN (BERU, UPT2) -22%
Spark Plug | BERU UPT2 Article №: UPT2
BERU Spark Plug UPT2
£ 4,49
£ 3,50
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Over 100 items in stock
  • Supplementary Info ULTRA TITAN
  • Thread Length [mm] 19
  • Electrode Gap [mm] 0,9
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  • Spark Plug 1 - Earthed Electrode, with gasket seat
  • Thread Size M14x1,25
  • Connector type SAE/M4
  • Quality/ Grade Poly-V Tit
  • Tightening torque from [Nm] 20
  • Tightening torque to [Nm] 30
  • Resistance from [kOhm] 3
  • Resistance to [kOhm] 10
  • Condition  New
Details
Spark Plug 0,9mm, 14mm, 3mm (BOSCH, 0 242 235 668) -22%
Spark Plug | BOSCH 0 242 235 668 Article №: 0 242 235 668
BOSCH Spark Plug 0 242 235 668
£ 3,99
£ 3,11
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Over 100 items in stock
  • Product line Nickel
  • Outer thread [mm] 14
  • Thread Length [mm] 19
  • Spark Position [mm] 3
  • Electrode Gap [mm] 0,9
  • Spanner Size 16
  • Thread Pitch [mm] 1,25
  • Connector type Gewindebolzen M4
  • Tightening Torque [Nm] 28
  • Number of Poles 2
  • Tightening angle [degrees] 90
  • Condition  New
Details
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