COMMON QUESTIONS

How often should I replace my car or truck plugs?

How often you change the spark plugs in your vehicle depends upon the type of plugs you use and how you drive the vehicle. Naturally, better plugs and easy driving conditions are optimal. LJK automotive spark plugs offer a 20K to 100K mile warranty, or 12 months according to the different models from the date of export. Go to the Catalog section of this website and use the online automotive parts catalog as a cross reference for your make, model and engine. 

How often should I replace my lawnmower plug?

Typically, lawnmower plugs are replaced seasonally but it depends upon the area of the country where you live. Our small engine plug warranty for non-commercial, household use offer your lawnmower covers the life of the original engine.

How do I find the right plug for my lawn & garden equipment?

Go to the Catalog section of this website and use the online lawn & garden catalog as a cross reference for your engine type and displacement. In addition, you can ask for assistance at any auto parts store listed in our "Where to Buy" guide. If you have the used plug, take it with you.

Will I need special tools to replace an LJK spark plug?

Check your owner’s manual for the correct size of the spark plug socket to remove the old plug and install a new LJK spark plug. If you are inspecting and/or cleaning an existing plug, we recommend cleaning the plug's threads with a wire brush to prevent damage to the threads inside the engine's head.

Where do I find the torque specifications for LJK plugs?

Go to the Tech Support menu for this website and click on the LJK Torque Chart for the plug that you are installing. You can also check your manufacturer's guide for exact plug torque information for your vehicle's engine.

Do I need to gap my new LJK spark plug?

Automotive spark plugs have a unique three-leg ground electrode and the powersport plug with its unique ground electrode are pre-gapped at the LJK factory to meet the O.E. requirements for the vehicles they are listed to fit. Do not attempt to change the gap. LJK Lawn & Garden plugs are gapped at the factory, but may require some adjustment to meet your O.E. engine requirements.

How do I know if my plug is fouled?

A fouled plug refers to a build up or coating of carbon deposits, oil or fuel on the plug's electrode tip and ceramic insulator. Sometimes the plug can be cleaned and re-installed. Typically, recurring problems with fouled plugs are indicative of other engine problems.

What is the difference between pre-ignition and detonation?

When something causes the air-fuel mixture to ignite prior to the spark plug firing, you have pre-ignition. Pre-ignition can be very damaging to your vehicle's engine. Detonation is the spontaneous combustion of the remaining mixture in the chamber after normal combustion is initiated by the spark plug. The key here is that detonation occurs after normal combustion. This often causes an engine "ping" that may indicate less than optimum performance.