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A spark plug does not generate high voltage by itself: an engine’s ignition coil supplies it, and the plug uses it to ignite the fuel-air mixture. Because live ignition components can cause potentially fatal injuries, do not try to produce an exposed spark as a demonstration. Diagnosis should follow the vehicle maker’s procedure and be handled by qualified service personnel.
How does a spark plug make a spark?
The spark plug is the final part of an engine’s ignition circuit. The ignition coil supplies high voltage to the plug; the electrical discharge across the plug’s electrodes creates the spark that ignites the mixture in the engine. The exact ignition-system design varies by vehicle, so there is no single universal setup or spark-making procedure. HELLA’s ignition-coil guidance describes the relationship between the coil and plug.
Why not make an exposed high-voltage spark?
HELLA warns: “During work on electronic ignition systems, contact with live components can result in potentially fatal injuries.” It says testing and repair should be carried out only by trained specialist staff. That warning applies even when the goal is simply to see a spark; do not handle ignition leads, plugs, coils, or other live components to create one.
OSHA’s workplace electrical rule generally calls for live parts that employees may be exposed to to be deenergized before work, subject to stated exceptions. It is a workplace safety requirement, not a consumer procedure for making or testing a spark. See OSHA 29 CFR 1910.333.
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- Often specified as original equipment, NGK spark plugs are the best combination of performance and longevity.
- Offering the Quality, Reliability and Durability You'd Expect from an OEM Manufacturer
- NGK is the world's largest supplier of OEM spark plugs
- Research Applications Prior to Purchase To Make Sure This OEM Part Fits Your Vehicle, Including Engine, Drivetrain and Quantity Needed.
- This Listing is for 4 Spark Plugs
How should a vehicle’s ignition spark be checked?
Use the vehicle manufacturer’s diagnostic procedure and have the work performed by qualified service personnel. Procedures and suitable equipment depend on the vehicle; do not treat one method or a single spark-voltage figure as universal.
For example, Ford’s On Board Diagnostics II PCED specifies “Spark Tester 303-D037 (D81P-6666-A) or equivalent” for its spark check. That supports using a purpose-built automotive spark tester when the applicable service instructions call for one—not improvising an exposed-spark setup or assuming the tool suits every vehicle.
Quick Recap
Best Value
- Bosch OE Fine Wire Double Iridium Spark Plugs feature both an iridium firing pin and an iridium ground electrode inlay that offer higher performance and 4X longer life compared to standard copper spark plugs
- 360-degree laser welded ultra-fine wire iridium firing pin provides better ignitability - reducing voltage requirements up to 24% - and enhanced durability
- Nickel-plated rolled threads provide maximum resistance to corrosion - ensuring the spark plugs remove easily from the cylinder head without galling - and do not require anti-seize during installation - saving time
- Bosch OE Fine Wire Double Iridium spark plugs are pre-gapped at the factory and ready to install right out of the box - gap adjustment prior to installation not required
- Meets or exceeds manufacturer design requirements for OE fit, form, and function for modern gasoline engines - including Gasoline Direct Injection (GDI) engines
Rank #4
- 4 pack NGK G-Power 7082 Spark Plug
- Genuine NGK Parts
- Includes original packaging and hardware
- Direct replacement auto parts
- Confirm vehicle fitment with Amazon Confirmed Fit
Rank #3
- Iridium Spark Plugs
- Designed to operate over a much wider heat range than ordinary plugs
- Resists carbon buildup and pre-ignition
- Patented triple gasket sealing process eliminates the possibility of combustion gas leakage
Rank #2
- G-Power Platinum
- Designed to operate over a much wider heat range than ordinary plugs
- Resists carbon buildup and pre-ignition
- Patented triple gasket sealing process eliminates the possibility of combustion gas leakage
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
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