FAQs

Frequently Asked Questions

Got a question about your Autolite® spark plugs or spark plugs in general? Chances are that we’ve been asked that question a lot. Check below for a list of Frequently Asked Questions.

Q: How do I order Autolite® catalogs?

The latest Autolite® catalog can be ordered free of charge by calling our distribution center toll free at 1-800-890-2075, menu option # 5.

Q: My dealer claims Autolite® plugs voids the warranty. Is this true?

If your local dealer is making a vehicle warranty contingent upon the use of their products, there may be a violation of Federal Law. As stated in the current Autolite® catalog as part of the Magnuson-Moss Warranty Improvement Act, "Using Autolite or other quality brand name spark plugs does not void vehicle warranty". Magnuson Moss warranty information is also available in the document titled "It's the Law".  This document is in Adobe pdf format. If you need the Adobe Reader that is required to read the Adobe pdf format, it is free to download from www.adobe.com/products/acrobat/readstep.html. Download and install the Adobe Reader, return to the Autolite® website, and refer to the documents.

You may also want to refer to the Federal Trade Commission Web site: www.ftc.gov for detailed information on the Magnuson-Moss Warranty Improvement Act.  

Q: How often should I replace spark plugs?

Autolite® does not establish recommendations for spark plug service intervals, but rather, follows the recommendations of the vehicle manufacturer. Autolite® spark plugs should be replaced at least as often as the vehicle manufacturers recommended change interval. We suggest you refer to your vehicle owners manual, local vehicle dealer, or refer to a reputable automotive service facility for information on appropriate mileage service intervals.

Q: How do I remove my spark plugs?

As a spark plug manufacturer and not an automobile service facility, professional liabilities prevent us from providing instruction on specific spark plug removal and installation. Spark plug installation may require the removal of engine components and may require that specific vehicle manufacturer procedures be followed to ensure proper service and safety. It is recommended that you follow the instructions listed in the vehicle service manual or as instructed by your local vehicle dealer or a reputable mechanic for specific spark plug service and replacement.

Quick Tips on Changing Your Plugs:

  • The Autolite® brand recommends that do-it-yourselfers follow manufacturer's recommendations on spark plug change intervals. It is good maintenance procedure to change all the plugs simultaneously.
  • Always be sure the engine is cool before beginning and gather all essential tools and products needed for the change, including replacement plugs, like Autolite® Double Platinum spark plugs, and mechanics gloves.
  • Rotate the spark plug boots 90-180 degrees before attempting to pull them off. This helps break the boots loose without tearing. Do not pull on the wire.
  • Before removing the old spark plugs, clean debris from the side of the plug area by using air pressure (compressed air or a bicycle pump will work just fine). This helps prevent any debris from falling into the cylinder and causing engine damage.
  • When gapping new plugs, use a round feeler gauge. It will give you a more accurate reading and will also help extend the life of the spark plug.
  • If having a hard time installing plugs, installers should use a piece of hose to extend their reach.
  • Look at the old spark plug tips to see if the engine has a problem that needs correcting. Bad plugs can cause overheating, rough running and other engine ailments.
  • If the exposed part of the plug and boot are covered in oil, be sure to repair the oil leak to help extend plug and wire life.
  • After final assembly, visually look to make sure all wires are properly routed so that they are not lying on the hot manifold or in the way of other objects that can cause damage.


If you have any questions regarding your Autolite spark plugs, call Autolite Answers(SM) to consult with one of our technicians. Autolite Answers  855-200-5200

 

Q: What is the function of a spark plug?

The spark plug is the last step in the ignition circuit.   It takes a voltage surge from the ignition coil using a controlled timing circuit and provides a path for the high voltage to be transferred into the ignition chamber where a spark ignites the compressed air fuel mixture within the cylinder. If everything is working properly and the correct amount of fuel is used, even burning of the compressed mixture results. The piston is pushed down, the crankshaft turns, and the engine runs efficiently. This provides maximum fuel economy and lowest exhaust emissions. 

Q: What is DIS?

DIS is different from standard electronic ignition systems in that the voltage surges from the coil passes through the plug wire to the plug. With the evolution of DIS, because spark plugs in a DIS system fire in a looped system rather than a single spark for those in a conventional system, the spark plug is required to be stronger and more robust. The Autolite® Double Platinum spark plug, which features platinum on both tips of the electrode is designed to withstand the added requirements of a DIS system. So when the DIS ignition system fires, the platinum on both tips of the electrode ensures the plug tip does not wear down AND maintains the gap thereby extending the life of the plug. With the extended life of the Autolite® Double Platinum spark plug, vehicle owners won’t have to incur the labor costs of changing their spark plugs as often since these plugs last 2 to 3 times longer. 

Q: What are the different types of spark plugs?

Spark plugs are available in different thread sizes and heat ranges. The various sizes and heat ranges are required to match engine requirements. They are also available with premium features such as platinum tipped electrodes for long life and small diameter (fine wire) electrodes for improved ignitability.

Q: Why do we need to change spark plugs?

One of the most economic ways to maintain an efficient engine and avoid wasting fuel is to change spark plugs at regular intervals. As spark plug electrodes wear, the voltage required to jump the gap increases. Under hard acceleration, high speeds or heavy loads, misfires can occur and that will waste fuel. Also, a rich fuel mixture or poor oil control can foul or coat the ceramic insulator on the spark plug tip. Fouling like excessive wear will promote misfires and can eventually cause the spark plug to stop functioning.

Q: How do I "read" a spark plug?

Look at the firing tip of your spark plugs while paying close attention to the condition and color of the ceramic insulator and the metal electrodes (known as the center wire and ground wire). If you have access to an Autolite® Master Catalog, you will find a series of pictures on the inside back cover to compare your spark plugs to. If not, simply observe the color first. Light tan or gray deposits are normal, and an indication that everything is working well. If everything is very white, with glazed deposits on the insulator tip, the spark plug is too hot for the engine, or at least for the conditions for which it was used. If black sooty deposits are present, a too rich fuel mixture is likely, or the spark plugs' heat range may be too cold for the application. Shiny black or oily deposits are an indication of bad oil seals and/or piston rings, and are not an indication that the spark plugs are at fault. Click here for more information.  Let our technicians help you at Autolite Answers(SM).  855-200-5200

Q: How (and why) do spark plugs need to be tightened for best performance?

It is very important to properly tighten spark plugs during installation. Too little torque can cause the spark plug to leak combustion gases and poor heat transfer of the plug seat to the cylinder head. Over-torque can damage both the spark plug and the threads in the engine head. Both can cause extensive engine damages. Your Autolite® Catalog lists the proper torque specs for various spark plug sizes. Check here for more information. 

Q: Do Autolite® spark plugs come pre-gapped from the factory?

Autolite® and all spark plug manufacturers offer spark plugs pre-gapped in the most popular gap sizes. Because of the many gap sizes required, no one offers spark plugs properly gapped for every application. Gapping has always been the job of the installer. You can be sure that the Autolite® spark plug recommended for your application has been engineered to meet the requirements of your engine, and that the gap can easily be adjusted as required. 

Q: What does it mean when spark plug tips are damaged or broken?

Spark plug tips, either the electrodes or the ceramic insulator, can be damaged in a variety of ways. Damage such as cracked ceramic or bent electrodes can be the result of shipping and handling or from mechanical damage within an engine. If an incorrect spark plug is used, it could come into contact with a piston or valve within the engine. Spark plugs can also be damaged by detonation or pre-ignition while in service. Click here for more information. 

Q: What is a fouled spark plug?

Spark plugs can become "fouled" by excessive fuel, oil or combustion deposits in the combustion chamber. Essentially what this means is that the spark plug insulator tip has become coated or covered by deposits which can conduct electricity. The spark plug has become "short circuited". In other words, the electrical current will now flow from the center wire over the insulator's deposits, to ground at the steel shell. It will not be able to produce a spark at the electrodes. Click here for more information. 

Q: What is a detonation?

Spark plug engineers will tell you that detonation is the result of two flame fronts colliding in the combustion chamber. What that means is that the air-fuel mixture has been ignited almost simultaneously in two locations within the combustion chamber of an engine. One flame front was probably ignited by a spark plug, while the second front was ignited spontaneously. The most common causes of detonation are too low octane fuel or over-advanced ignition timing. The result produces the characteristic "knock" or "ping" sound associated with detonation. If left unchecked, it can cause serious engine damage. Expect broken or bent valves and spark plug tips. Click here for more information. 

Q: What is pre-ignition?

Pre-ignition is similar to detonation, but only one flame front is ignited in advance of the spark. The ignition point can again be a hot spot, but the hot spot will usually be glowing deposits or metal such as the spark plug electrodes or an exhaust valve. A spark plug center wire may start to glow and cause pre-ignition if the spark plug has too hot of heat range for the application. A lean fuel mixture, a defective EGR valve or over-advanced timing may also cause this problem. Sustained pre-ignition will likely melt spark plug electrodes, and it can burn holes in valves and pistons. Click here for more information. 

Q: What are the wires' function in an engine?

Containing between 20,000 and 50,000 volts, their role in the engine is to guide high voltage electricity from the coils to the spark plugs, ultimately leading to ignition firing. Depending on the Original Equipment requirements for each application, the suppressor, mag or copper cores in Autolite®'s premium wires deliver maximum voltage without the radio interference that sometimes exists with other wire sets. Their high-tech nylon reinforcement provides increased terminal retention and improved jacket adhesion, which makes the ignition wires less likely to tear away from their insulation.

Q: What are the signs that my wires need to be changed and is there a good preventative change time?

Spark plug wires should be changed when they start to become hard or inflexible, or look dry and cracked. If one wire fails, it's probably time to change them all. Spark plug wire life varies greatly depending on a number of factors, but you should change them at least as often as manufacturer's recommendations. Cracked wires can cause misfires resulting in poor performance. This can also cause cross firing, which can result in pre-ignition. An accumulation of grease or oil on the wires may lead to early replacement, and lastly, corrosion at the spark plug terminal or distributor cap may also lead to premature failure.

Q: What is unique about Autolite® Professional Series Ignition Wires?

Automotive do-it-yourself (DIY) consumers and installers who want products that meet Original Equipment Service (OES) for fit, form and performance can use Autolite® Professional Series Ignition Wires. These premium wire sets not only meet OES design requirements, but also when regularly maintained, help avoid the vehicle misfires that result in wasted fuel. They feature High Temperature pre-greased silicone boots, a high temperature silicone jacket, corrosion resistant clip locking terminals, MAG and Copper Core wires where applicable, and increased terminal retention and strength properties. 

Q: How do you install ignition wires?

The best way to replace spark plug wires is one at a time. Start with the longest wire on the engine, and replace it with the longest wire in the set. Work your way down to the shortest wire, until all are used. Do not remove more than one at a time, so you cannot misplace them. Be careful to route the wires using existing clips and retainers so that the new wires cannot come into contact with the exhaust manifold or other high temperature parts. Firmly grasp the spark plug boot and push it over the spark plug until the terminal engages. Likewise push the distributor end firmly into the distributor cap until the terminal engages and the boot is securely sealed. It is not always easy to determine the length of the original wires on the engine. If you find a longer one than previous, carefully remove the new wire and install it in the longer route. 

Q: How can I determine what kind of engine I have?

Most cars have an emissions decal under the hood that will indicate the engine size. You can also match up your VIN code number with the Autolite® applications. For most cars use the eighth digit in the VIN number. The VIN can be found on the front corner of your dashboard or on your title or registration. Click here for more information or call our technicians at Autolite Answers(SM) at 855-200-5200. 

Q: How do you match the style and heat range of the OE spark plug?

We use what is called a "rating engine" to match up plugs. The process begins by buying the OE spark plugs and carefully measuring them. Our engineers then match the physical qualities with several Autolite® plugs. Then we run the OE spark plug in our rating engine. The data from this engine tells us the heat range of the OE spark plug. We use this information to precisely match an Autolite® spark plug to both the heat range and dimensions of the Original Equipment plug. 

Q: What are the benefits of using a .6mm Finewire Iridium Enhanced Motorcycle that originally had a copper core plug?

  • 0.6mm finewire design with Sport V-trim ground electrode engineered to offer improved ignitability and durability over a standard plug
  • Up to 26% quicker starts than leading standard plugs
  • More focused ignition to prevent fouling than leading standard plug
  • More horsepower and better fuel efficiency than standard plug
  • Larger flame kernel for more complete burn, faster starts and better performance & fuel efficiency
  • Optimum Performance
  • Less firing voltage for more coil dwell time

Q: Should I still use a .6mm Finewire Iridium Enhanced spark plug even if I install a new plug every season?

Yes, you will gain all of the benefits listed above from using a Premium spark plug compared to that of a standard plug. The Autolite Xtreme Sport® spark plugs extract optimal performance, better fuel efficiency and quicker starts.

Q: Is the Autolite Xtreme Sport® Spark Plug resistant to fouling?

Yes, the extended tip and lower required voltage to fire Autolite Xtreme Sport® spark plugs help prevent fouling by providing a more focused ignition.  

Q: Can I use an Autolite Xtreme Sport® Spark Plug in my 2-stroke engine?

Yes you can, it will give you up to 26% quicker starts than leading standard plugs and better ignition system performance. The benefits of the finewire design in Autolite Xtreme Sport® also provide improved fouling performance; fouling is a common problem in 2-stroke engines