I am curious about the ignition system in my lawn mower. I know that a spark plug creates a high-voltage spark, and I know in my car the electricity for the spark comes from the ba... HEAT RANGE CHART - COPPER PLUS SPARK PLUG / STOCK NUMBER Federal-Mogul Document #1521 Thread Size Heat Range Non-Resistor Stock No. Resistor Stock No. Non-Resistor Stock NO. Resistor Stock No. 10mm 1/4" Rch. 5/8" Hex NORM UY6 842 Auxiliary Gap 10mm 5/16" Rch. NORM Y82 877 14mm Hex 10mm .492" Rch. HOT 5/8" Hex COLD Z6 889 Z9Y 808 10mm 1/2" Rch ... Aug 11, 2022 · 268 posts · Joined 2022. #21 · Aug 13, 2022. Here, put "champion rule for spark plug heat range" in google. "According to Champion Spark Plugs, for normally aspirated, gasoline-fueled engines, a good rule of thumb is to go about one heat range colder for each full point in compression ratio increase from 9:1 through about 12.5:1, and two heat ... The Solana Foundation is working to integrate AI into its network with a ChatGPT plug-in developed by Solana Labs. As the artificial intelligence market continues to heat up, a num...E3 Racing Spark Plugs incorporate the Edge-to-Edge patented DiamondFIRE technology design that directly sends the spark travel towards the air-fuel mixture which maximizes the burn. The result is a faster flame kernel, a more complete combustion, greater power and higher fuel efficiency. These spark plugs produce excellent heat transfer, with ...Oil appears in the spark plug well when there is a leaking valve cover gasket or when an O-ring weakens or loosens. Each spark plug has an O-ring that prevents oil leaks. When the ...Iridium. Iridium is said to be six times harder and eight times stronger than platinum with a 700° higher melting point. Iridium spark plugs have extremely fine electrodes while retaining excellent wear characteristics. Thanks to this strength, iridium spark plugs can last up to 25% longer than comparable platinum spark plugs.Para obtener la aplicación correcta de su vehículo, por favor referirse a la sección correspondiente dentro de esta guía. 410. Competitor # NGK Stock # NGK Part # Competitor # NGK Stock # NGK Part # Competitor # NGK Stock # NGK Part # ACDelco. R43T6 7240 YR55 R43TS 2771 UR5 R43TS6 2248 UR55 R43TSK 2771 UR5 R43TSX …Most spark plug manufacturers recommend that the tip temperature remain between 500° C and 850° C. Heat ranges are designated by each spark plug manufacturer with a number. In broad terms, spark plugs are often referred to as “hot plugs” or “cold plugs.”. A cold plug has a shorter insulator nose length—the distance from tip to spark ... To prevent pre-ignition and overheating the optimum spark plug tip temperature generally needs to be below about 800°C (1472°F). So there we have the optimum temperature range for our spark plug – somewhere between around 500 to 800°C (932°F to 1472°F). An example is: DPR5EA-9; 2887. DPR5EA-9 is the part number and 2887 is the stock number. The exception to this is racing plugs. An example of an NGK racing plug is R5671A-11. Here, R5671A represents the plug type and -11 represents the heat range. The stock number is 6596. NGK lists a design symbols chart in the front of every spark plug catalog. A conventional copper electrode replacement for an AC Delco #10 Rapid Fire platinum tip spark plug is a AC Delco R43T spark plug. If you want one step hotter than AC Delco R43T, you can use AC Delco R44T. An AC Delco R45T spark plug is two steps hotter than a AC Delco R43T spark plug. Usually, an AC Delco spark plug that is only one step hotter ...Autolite spark plug heat range. I am running an Autolite 3924 in my 86 GT, Edelbrock RPM heads, mild cam, 9.6:1 flat tops, carbureted. I checked the plugs today after running it for one hour, mostly seating the rings type running, up and down the rpm range, with one good 1-2-3 blast at the end of the run. I drove back home and looked at the ...If it the heat range is too hot, your engine could experience detonation, pre-ignition, or power loss. Most spark plug manufacturers recommend that the tip temperature remain between 500-850 degrees Celsius. Diagram courtesy of NGK Spark Plugs. Heat ranges are designated by each spark plug manufacturer with a number.COVID-19 may not affect Plug Power's underlying business. But don't take that as a reason to buy red-flag-ridden PLUG stock. COVID-19 may not affect Plug Power's underlying busines...Choosing the right spark plugs for your vehicle is essential for its optimal performance and fuel efficiency. With so many options available in the market, it can be overwhelming t...ACDelco Spark Plugs feature only high-quality parts to help ensure durability and consistent performance: Electrodes built on a foundation of iridium, platinum or copper. 100% copper cores. Spark plugs are protected with one-piece ceramic insulators. We offer a full line of ACDelco Spark Plug products. Whether you are choosing from our iridium ...However, because of more exposure to high temperature combustion gases and because ground electrode becomes longer, heat resistance and durability decrease. The higher the level of tuning, the greater the need is to use a less projecting type. As the level of tuning is increased, so does the need for higher heat range.The spark plug works as a heat exchanger by pulling unwanted thermal energy away from the combustion chamber, and transferring the heat to the engine’s cooling system. The heat range is defined as a plug’s ability to dissipate heat. The rate of heat transfer is determined by: The insulator nose length. Gas volume around the insulator nose.The difference between hot and cold spark plugs lies in their ceramic insulation. Learn how hot and cold plugs are different in ignition systems in this article. Advertisement Car ...Firstly, consider the heat range. A colder spark plug, such as the HD-6R12 plug, is ideal for high-performance engines or those running at higher RPMs. ... A spark plug chart helps in choosing the right spark plug for your application, whether it’s Iridium spark plugs or standard plugs. It ensures that during service, when using a torque ...NGK.comA worn spark plug not only wastes fuel but also strains the whole ignition system because the expanded gap (due to erosion) requires higher voltages. Normal rates of gap growth are as follows: Four-Stroke Engines: 0.01~0.02 mm/1,000 km (0.00063~0.000126 inches/1,000 miles)The numbers on spark plugs indicate properties such as spanner width and design, heat rating, thread length, construction features and electrode distances. Different manufacturers ...All the right spark plugs, recommended by Ford Motor Company. The Motorcraft ® name means quality, performance, reliability and confidence. All of these can be found in each Motorcraft ® spark plug. Motorcraft ® spark plugs are available for a broad range of applications, including domestic and import cars and trucks of all makes and sizes.The spark plug heat range has no relationship to the electrical energy transferred through the spark plug. The heat range of a spark plug is the range in which the plug works well thermally. The heat rating of each NGK spark plug is indicated by a number; lower numbers indicate a hotter type, higher numbers indicate a colder type. This means the spark plug will heat up easily and reach its optimal operating temperature. High performance engines on the other hand produce a large amount of heat, hence a high heat range (or cold) spark plug such as a 10 heat range needs to be used to resist the heat developed by the engine. Several factors influence the heat range of a ... Find out how to fix a rough running lawn mower engine by adjusting the spark plug gap, cleaning air and fuel filters, and switching to ethanol-free gas. Expert Advice On Improving ...NGK Spark PlugsObject moved to here.HEAT RANGE CHART - COPPER PLUS SPARK PLUG / STOCK NUMBER Federal-Mogul Document #1521 Thread Size Heat Range Non-Resistor Stock No. Resistor Stock No. Non-Resistor Stock NO. Resistor Stock No. 10mm 1/4" Rch. 5/8" Hex NORM UY6 842 Auxiliary Gap 10mm 5/16" Rch. NORM Y82 877 14mm Hex 10mm .492" Rch. HOT 5/8" Hex COLD Z6 889 Z9Y 808 10mm 1/2" Rch ...Autolite spark plug heat range. I am running an Autolite 3924 in my 86 GT, Edelbrock RPM heads, mild cam, 9.6:1 flat tops, carbureted. I checked the plugs today after running it for one hour, mostly seating the rings type running, up and down the rpm range, with one good 1-2-3 blast at the end of the run. I drove back home and looked at the plugs.Why is spark plug heat range important? A. Heat range is important because too hot of a heat range can create . engine damaging pre ignition. Too cold of a heat range will allow deposits to build on the spark plug (Fouling) creating inconsistent ignition. Q. Why do spark plug replacement intervals vary from application to . application?The AC Delco Spark Plug Decoder Table Prefix and suffix letters are used to identify a specific type plus the numbers relate to thread size and heat range. For example, the R45TS spark plug shown is: · R - Resistor · 4 - 14 mm Thread · 5 - Heat Range (range 1-5 start with a 3) · T - Taper Seat (No T for a gasketed plug)Check for faulty or sticking choke, overly rich fuel mixture, ignition problems, leaking fuel injectors, or spark plug heat range is too cold.Appearance - Firing tip is damp with gasoline, usually the odor of fuel is present on the spark plug. The insulator is often tinted the color of charcoal.These usually look WET and smell of gasoline.- NGK Spark Plugs. WHY ARE THERE DIFFERENT HEAT RANGES? It is a common misconception that spark plugs create heat. They don’t. the spark plug heat range only …Why is spark plug heat range important? A. Heat range is important because too hot of a heat range can create . engine damaging pre ignition. Too cold of a heat range will allow deposits to build on the spark plug (Fouling) creating inconsistent ignition. Q. Why do spark plug replacement intervals vary from application to . application?NGK BKR8EIX (Iridium) Denso IK24 (Iridium) Bosch FR5DTC (Copper) Bosch F5DPOR (Platinum/Side Fire)*. * - Many members have found real good luck with the Bosch F5DPOR's. Below is a quick cross-reference list for all the plugs listed above in Heat Range: ** - Audi/VW Factory 1.8T/2.7T Heat Range.The spark plug heat range has no relationship to the electrical energy transferred through the spark plug. The heat range of a spark plug is the range in which the plug works well thermally. The heat rating of NGK spark plugs is indicated by a number; lower numbers indicate a hotter type, higher numbers indicate a colder type.The knock sensor in a Nissan Xterra performs a critical job. It "listens" to your engine to make sure that the engine is firing properly. If too much fuel gets into the engine, the...Spark Plug Heat Range Explained. A Spark Plug's heat range is a measure of its ability to conduct heat away from its firing end. A COLDER or 'harder' spark plug is more suited to a hotter running engine (i.e. high performance, high revving, tuned or driven very hard), the shorter heat path will conduct heat more quickly, ensuring that the tip ...A worn spark plug not only wastes fuel but also strains the whole ignition system because the expanded gap (due to erosion) requires higher voltages. Normal rates of gap growth are as follows: Four-Stroke Engines: 0.01~0.02 mm/1,000 km (0.00063~0.000126 inches/1,000 miles)Spark plug manufacturers use a heat range numbering system that is not universal, meaning that a 10-heat range in Champion may not be the same as a 10-heat range in NGK or Autolite. The numbering system can even vary from one brand to another. For Champion, Autolite, and Bosch, higher numbers represent hotter plugs, while for NGK, Denso, and ...Rather, the heat range is a measure of the spark plug's ability to remove heat from the combustion chamber. The heat range is determined by the insulator nose length and its ability to absorb and transfer combustion heat, the gas volume around the insulator nose, and the materials/construction of the center electrode and porcelain insulator.In ... The range of thermal values for BRISK spark plugs extend from the warmest to the coldest, namely 19, 18, 17, 15, 14, 12, 10 and 08. "Hot" spark plugs remove heat from the combustion area relatively slowly. They have a longer insulator tip and they achieve a temperature higher than the deposition zone relatively fast. Incorrect spark plug heat range, a loose spark plug, improper ignition timing, or a lean air/fuel ratio are all potential contributors to an overheated engine. You need to change the spark plug. Source: golfmk7. 5. Lead Fouling. Yellowish-brown deposits on the insulator nose are a telltale sign of lead fouling.ACCEL HP Spark Plugs are made with a Copper core which is a better conductor than Platinum and Iridium. They deliver a stronger spark especially in high performance applications where high combustion pressures are present. Copper is much better at dissipating heat than other materials which lessens the chance of a misfire.Nov 5, 2022 · The spark plug heat range scale typically ranges from 2 to 12, with 2 being the coldest and 12 being the hottest. It’s important to note that the heat range scale may vary slightly depending on the manufacturer. When selecting a spark plug, it’s crucial to choose the appropriate heat range for your engine. This means the spark plug will heat up easily and reach its optimal operating temperature. High performance engines on the other hand produce a large amount of heat, hence a high heat range (or cold) spark plug such as a 10 heat range needs to be used to resist the heat developed by the engine. Several factors influence the heat range of a ...The spark plug with a heat range of 6 is considered hotter than the one with a heat range of 9. This means that the spark plug with a heat range of 6 will retain …The numbers on spark plugs indicate properties such as spanner width and design, heat rating, thread length, construction features and electrode distances. Different manufacturers ...When To Change The Spark Plug Cables Of Your Car's Engine. Like the spark plugs, the ignition coils or cables would need replacing every 30,000 to 70,000 miles. In some …Since each application requires a different heat range of spark plug, a typical street-style spark plug usually won't cut it. Fortunately, E3's R&D department is working overtime to introduce its ...Heat Range Reference. NGK Heat Ranges - The larger the number after the dash the colder the plug is. Example a R5671A-7 (a good street/strip plug) is a cold plug where a R5671A-10 is a very cold plug used for large 400hp and up nitrous and other power adder applications) Autolite Heat Ranges - The larger the last digit in the part number, the ...Vehicle. Spark Plug Heat Ranges Explained & Cross Reference Table. Learn what a spark plugs heat range means & use our cross reference table. Using a spark plug …A very expensive heat range test can be performed however a more viable option is to start with a colder heat range spark plug and perform some testing. As mentioned a spark plug operates in the range temperature 450 – 870°C, at 450°C carbon deposits being to burn off and if a plug may have a very black insulator nose at a lower temperature.Incorrect spark plug heat range, a loose spark plug, improper ignition timing, or a lean air/fuel ratio are all potential contributors to an overheated engine. You need to change the spark plug. Source: golfmk7. 5. Lead Fouling. Yellowish-brown deposits on the insulator nose are a telltale sign of lead fouling.Incorrect spark plug heat range, a loose spark plug, improper ignition timing, or a lean air/fuel ratio are all potential contributors to an overheated engine. You need to change the spark plug. Source: golfmk7. 5. Lead Fouling. Yellowish-brown deposits on the insulator nose are a telltale sign of lead fouling.Effects of humidity and selection of proper heat range.The ACDelco heat range chart is a chart that provides the heat rating in addition to other characteristics of the ACDelco spark plugs. The heat rating indicates the thermal characteristic of the spark plug, or how hot or how cold the spark plug is. The chart details the plug identification table. It consists of possible spark plug prefix values ...NGK’s performance and heat dissipation capacity cannot beat that of Champions. Conductivity. Champion Spark Plug is better and has higher conductivity than NGK. NGK spark plugs have better and higher conductivity. Size. Tread Diameter:0.551. Gap Size: 0.40 inch. Type. Copper plus spark plug.ACDelco Spark Plugs feature only high-quality parts to help ensure durability and consistent performance: Electrodes built on a foundation of iridium, platinum or copper. 100% copper cores. Spark plugs are protected with one-piece ceramic insulators. We offer a full line of ACDelco Spark Plug products. Whether you are choosing from our iridium ...This is a *basic* table of approximate spark plug heat range equivalents from manufacturers NGK, Denso and Champion. Note that Champion have further additional …This process involves making a pull (on a dyno or a pass), and shutting down the engine ASAP so the reading isn't tainted by idle time. Then the plugs are pulled and inspected. After a change is ...Citrix Receiver is the software you use on your own device to work remotely while connected to your organization's network. The Online plug-in is one of several tools that bring ad... Replace with a new set of Autolite spark plugs. 6. GLAZING Recommendation: Spark plug is operating too hot at high speeds. Replace with a colder heat range of Autolite spark plug. 7. CARBON FOULED Recommendation: Spark plug heat range is too cold and/ or caused by extensive low-speed, short distance driving. Replace with the correct heat range ... Tenneco's Champion ® Industrial Spark Plugs is an industry-leading brand name and technology servicing all applications and markets throughout the world. Champion was the first to pioneer ignition products for industrial applications and, for over 100 years, is still driving the market in product excellence. Champion's industrial products ... DENSO Spark Plug Heat Range. Published4 July 2019. Ask An Expert: Heat range is one of the most important and often misunderstood factors when choosing the correct spark plug for your engine. Let our DENSO expert explain how it all works. acdelco.com.au How is Heat Range Engineered? Heat is conducted away from the firing tip through the (1) insulator to (2) the spark plug shell to (3) the cylinder head. Thus, heat ranges are primarily controlled by the length of the insulator through which the heat must travel before escaping to the cylinder head. Other factors effecting Heat Range are theReplace with a new set of Autolite spark plugs. 6. GLAZING Recommendation: Spark plug is operating too hot at high speeds. Replace with a colder heat range of Autolite spark plug. 7. CARBON FOULED Recommendation: Spark plug heat range is too cold and/ or caused by extensive low-speed, short distance driving. Replace with the correct heat …Dec 10, 2023 · The heat range of a Champion spark plug is indicated within the individual part number. The number in the middle of the letters used to designate the specific spark plug gives the heat range. For instance, if a Champion spark plug’s number is RCJ6Y, the heat range is 6. With Champion spark plugs, a higher number in the middle of the part ... RN7YC; now Champion 332. RN9YC; now 415. RN11YC4; now 322 (also given for N10Y) RN12YC; now 404. RN14YC; now 405. Andy referenced www.sparkplugs.com where I pulled the table below showing the Champion naming convention for their plugs. The higher the number, the hotter the plug. E3 spark plug heat range chart - motorcraft spark plug wire set - Web: http://www.autopartsstoresus.com/spark-plugs/spark-plugs.htmlThe heat range of a Champion spark plug is indicated within the individual part number. The number in the middle of the letters used to designate the specific spark plug gives the ... Ignition. ACCEL HP Spark Plugs are made with a Copper core which is a better conductor than Platinum and Iridium. They deliver a stronger spark especially in high performance applications where high combustion pressures are present. Copper is much better at dissipating heat than other materials which lessens the chance of a misfire. temperature of the tip of the spark plug. If the heat range is too cold, the deposits will not burn off the tip and the spark plug will foul. If the spark plug heat range is too hot, pre-ignition can occur. A switch in heat range of the spark plug will change the temperature of the spark plug tip by 70-120 degrees. The operating temperature of a spark plug varies between 450-870°C. At 450°C the spark plug reaches its self cleaning temperature; this means that carbon deposits which are produced during combustion are actively burnt off the insulator nose.AGSF32C - Short name: SP447. Recommended for 1993 Cobra, GT40 Heads. A = Thread Diameter = 14 mm. G = Reach = .708" Conical Seat. S = Plug Characteristic = Suppressor (Carbon) F = Plug Characteristic = Conical Seat. 3 = Heat Range = Cold (Stock) 2 = Tip Configuration = Extended (Power) Tip. C = Plug Characteristic = Copper Core Electrode.Money's picks for the best plug-in hybrid SUVs in 2023, including top choices for value, handling, safety, technology and features. By clicking "TRY IT", I agree to receive newslet...No longer necessary as modern spark plug coatings work as a releasing agent and should be installed dry. Anti-seize can alter the tightening torque up to 20%, increasing risk of breakage. Anti-seize can create heat …of the spark plug. If the heat range is too cold, the deposits will not burn off the tip and the spark plug will foul. If the spark plug heat range is too hot, pre-ignition can occur. A …and material, plugs produced by various manufacturers do not have exactly the same heat range. Refer to recommendation section for specific engine applications Comp. Part# NGK STK # NGK # Comp. Part# NGK STK # NGK # Comp. Part# NGK STK # NGK # 44 3510 B6S 41-963 7740 PTR5C-13 45FFS 6222 BPR5HS 45 3210 B4 41-965 2467 PTR5A-13 …Feb 2, 2010 · According to AC's chart, prefix is the letters before the numbers and suffix is the letters after the numbers. That would make the plugs (if AC), M=marine. R=resistor. 4=14mm thread. 3=heat range. T=tapered seat shell design. That would make your recommended plugs a colder marine type plug designed for a boat engine. Jan 28, 2022 ... While ngk's 4 heat range is closer to champion 13-14 range. ... There is a spark plug cross reference chart in the Tech Editors Desk section of ...The heat rating is a measure of the amount of heat dissipation.The heat range of a spark plug is the range in which the plug works well thermally. The heat rating of each NGK spark plug is indicated by a number; lower numbers indicate a hotter type, higher numbers indicate a colder type. Effect of Selecting Wrong Heat Range.Spark Plug Thread Size: 14mm . Spark Plug Reach (in.): 0.750 in. Spark Plug Reach (mm): 19.05mm . Manufacturer Heat Range: 12 . Shorty Spark Plug: ... Champion racing spark plugs position the spark approximately 1/16 in. into the combustion chamber and feature colder heat ranges that use a shortened ground electrode. This is designed to …Recently, I’ve talked quite a bit about connecting to our creative selves. (Yes, everyone is creative!) One Recently, I’ve talked quite a bit about connecting to our creative selve...Spark plugs with a high degree of heat dispersal are called high heat range (cold type) and those with a low degree of heat dispersal are called low heat range (hot type). This is largely determined by the temperature of the gas inside the combustion chamber and the spark plug design.However, because of more exposure to high temperature combustion gases and because ground electrode becomes longer, heat resistance and durability decrease. The higher the level of tuning, the greater the need is to use a less projecting type. As the level of tuning is increased, so does the need for higher heat range.The spark plug heat range has no relationship to the electrical energy transferred through the spark plug. The heat range of a spark plug is the range in which the plug works well thermally. The heat rating of NGK spark plugs is indicated by a number; lower numbers indicate a hotter type, higher numbers indicate a colder type.
To prevent pre-ignition and overheating the optimum spark plug tip temperature generally needs to be below about 800°C (1472°F). So there we have the optimum temperature range for our spark plug – somewhere between around 500 to 800°C (932°F to 1472°F).. Diarrhea and burping bad smell
Spark Plugs. You never forget your first Champion ®. Our spark plugs have been improving engine performance since 1907. Choose your next Champion from the range of plugs that live up to the legacy of this iconic brand.The 302 plug differs from the 200 plug only in heat range. The 200 plug is signifantly hotter. This is due to the poor air flow plus the poor chamber design. A hotter plug is required to light the mixture off properly and keep the plug from fouling on unatomized fuel droplets. Now, I swapped heads on my 250 (same plug as 200).The operating temperature of a spark plug varies between 450-870°C. At 450°C the spark plug reaches its self cleaning temperature; this means that carbon deposits which are produced during combustion are actively burnt off the insulator nose.A good rule of thumb: use one heat range colder for every 75–100hp added. In identical spark plug types, the difference from one full heat range to the next is the ability to remove 70°C to 100°C from the combustion chamber. The heat range numbering system used by spark plug manufacturers is not universal.Explanation of a Spark Plugs Heat Range from NGK Spark Plugs USAIridium. Iridium is said to be six times harder and eight times stronger than platinum with a 700° higher melting point. Iridium spark plugs have extremely fine electrodes while retaining excellent wear characteristics. Thanks to this strength, iridium spark plugs can last up to 25% longer than comparable platinum spark plugs.The spark plug heat range scale typically ranges from 2 to 12, with 2 being the coldest and 12 being the hottest. It’s important to note that the heat range scale may vary slightly depending on the manufacturer. When selecting a spark plug, it’s crucial to choose the appropriate heat range for your engine.Most spark plug manufacturers recommend that the tip temperature remain between 500-850 degrees Celsius. Diagram courtesy of NGK Spark Plugs. Heat ranges …The AC Delco Spark Plug Decoder Table Prefix and suffix letters are used to identify a specific type plus the numbers relate to thread size and heat range. For example, the R45TS spark plug shown is: · R - Resistor · 4 - 14 mm Thread · 5 - Heat Range (range 1-5 start with a 3) · T - Taper Seat (No T for a gasketed plug)Has your sales team lost their spark? Here are the ways leaders can prevent, recognize, and manage sales burnout. Sales | Tip List REVIEWED BY: Jess Pingrey Jess served on the foun... HEAT RANGE CHART - COPPER PLUS SPARK PLUG / STOCK NUMBER Federal-Mogul Document #1521 Thread Size Heat Range Non-Resistor Stock No. Resistor Stock No. Non-Resistor Stock NO. Resistor Stock No. 10mm 1/4" Rch. 5/8" Hex NORM UY6 842 Auxiliary Gap 10mm 5/16" Rch. NORM Y82 877 14mm Hex 10mm .492" Rch. HOT 5/8" Hex COLD Z6 889 Z9Y 808 10mm 1/2" Rch ... A new reversible USB plug is likely to hit the market next year. A new reversible USB plug is likely to hit the market next year. The next generation of USBs is currently being dev...Replace with a new set of Autolite spark plugs. 6. GLAZING Recommendation: Spark plug is operating too hot at high speeds. Replace with a colder heat range of Autolite spark plug. 7. CARBON FOULED Recommendation: Spark plug heat range is too cold and/ or caused by extensive low-speed, short distance driving. Replace with the correct heat range ...Spark plugs with a high degree of heat dispersal are called high heat range (cold type) and those with a low degree of heat dispersal are called low heat range (hot type). This is largely determined by the temperature of the gas inside the combustion chamber and the spark plug design..