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Spark Plug

919 items

Shop precise fit replacement Spark Plug to maintain and improve your vehicle's performance. Find the right parts for your make and model, backed by excellent customer service at A-Premium.

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8 Pack Iridium Spark Plug | A-Premium APSP0108 Pack Iridium Spark Plug | A-Premium APSP010
A-Premium®Part # APSP010
8 Pack Iridium Spark Plug | A-Premium APSP010
4.7272 Reviews
$38.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2005 - 2008 Chrysler 300, 2007 - 2008 Chrysler Aspen, 2006 - 2008 Dodge Charger, 2004 - 2008 Dodge Durango, 2005 - 2008 Dodge Magnum, 2003 - 2008 Dodge Ram 1500, 2003 - 2008 Dodge Ram 2500, 2004 - 2008 Dodge Ram 3500, 2006 - 2008 Jeep Commander, 2005 - 2008 Jeep Grand Cherokee
Check if this fits your vehicle
Item LocatedUnited States
Quantity8
MaterialIridium + Platinum
Part interchange
2313, LZTR4AIX11, AI5263
item #10051HX6
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6 Pack Iridium Spark Plug | A-Premium APSP005
A-Premium®Part # APSP005
6 Pack Iridium Spark Plug | A-Premium APSP005
4.7272 Reviews
$35.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2007 - 2010 Audi Q7, 2008 - 2010 Porsche Cayenne, 2018 - 2018 Volkswagen Atlas, 2019 - 2019 Volkswagen Atlas, 2009 - 2017 Volkswagen CC, 2006 - 2010 Volkswagen Passat, 2012 - 2018 Volkswagen Passat, 2009 - 2010 Volkswagen Passat CC, 2007 - 2017 Volkswagen Touareg
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Item LocatedUnited States
Quantity6
MaterialIridium + Platinum
Part interchange
1961, ILZKR7A, 101905622
item #100527CD
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6 Pack Iridium Spark Plug | A-Premium APSP065
A-Premium®Part # APSP065
6 Pack Iridium Spark Plug | A-Premium APSP065
4.7272 Reviews
$26.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2001 - 2004 Chevrolet Tracker, 2007 - 2008 Chrysler Crossfire, 1993 - 1997 INFINITI J30, 1996 - 2002 Honda Passport, 1999 - 2000 Mercedes-Benz C280, 1996 - 2001 INFINITI I30, 2002 - 2005 Hyundai Sonata, 2003 - 2003 Mercedes-Benz ML320, 2007 - 2012 Hyundai Veracruz, 1993 - 1995 Ford Taurus, 2001 - 2002 Mercedes-Benz C320, 2001 - 2003 Isuzu Rodeo Sport, 2007 - 2011 Hyundai Azera, 1995 - 2000 Dodge Avenger, 2005 - 2006 Chrysler Crossfire, 1998 - 1999 Acura SLX, 2003 - 2004 Mercedes-Benz ML350, 1996 - 1998 Acura TL, 2002 - 2003 Isuzu Axiom, 2001 - 2002 Mercedes-Benz C240
Check if this fits your vehicle
Item LocatedUnited States
Quantity6
MaterialIridium + Platinum
Part interchange
5464, BKR5EIX11, 7090, BKR5EGP, 2271, PFR5C11, 2382, BKR5ES11, 
...View more
item #10051K71
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8 Pack Iridium Spark Plug | A-Premium APSP264
A-Premium®Part # APSP264
8 Pack Iridium Spark Plug | A-Premium APSP264
4.7272 Reviews
$47.99
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2-year warranty
90 days free return
Fits 1998 - 2000 Lexus GS400, 2001 - 2007 Lexus GS430, 2003 - 2009 Lexus GX470, 1990 - 1994 Lexus LS400, 1997 - 2000 Lexus LS400, 2001 - 2006 Lexus LS430, 1998 - 2007 Lexus LX470, 1992 - 2000 Lexus SC400, 2002 - 2010 Lexus SC430, 2005 - 2006 Mercedes-Benz C55 AMG, 2004 - 2006 Mercedes-Benz CLK55 AMG, 2006 - 2010 Mercedes-Benz SLK55 AMG, 2003 - 2009 Toyota 4Runner, 1998 - 2007 Toyota Land Cruiser, 2005 - 2009 Toyota Sequoia, 2005 - 2009 Toyota Tundra, 2007 - 2010 Volvo S80, 2005 - 2011 Volvo XC90
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Item LocatedUnited States
Quantity8
MaterialIridium + Platinum
Part interchange
3297, SK20R11, 9091901210
item #1000PYPH
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4 Pack Iridium Spark Plug | A-Premium APSP241
A-Premium®Part # APSP241
4 Pack Iridium Spark Plug | A-Premium APSP241
4.7272 Reviews
$29.99
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2-year warranty
90 days free return
Fits 2013 - 2018 Hyundai Santa Fe Sport, 2011 - 2014 Hyundai Sonata, 2015 - 2017 Hyundai Sonata, 2011 - 2015 Hyundai Sonata, 2011 - 2016 Kia Optima, 2017 - 2018 Kia Optima, 2011 - 2016 Kia Optima, 2016 - 2018 Kia Sorento, 2011 - 2020 Kia Sportage
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Item LocatedUnited States
Quantity4
MaterialIridium + Platinum
Part interchange
92422, SILZKR8E9G
item #10051WS4
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4 Pack Iridium Spark Plug | A-Premium APSP075
A-Premium®Part # APSP075
4 Pack Iridium Spark Plug | A-Premium APSP075
4.7272 Reviews
$22.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2010 - 2014 Honda CR-V, 2008 - 2012 Honda Accord, 2012 - 2015 Honda Crosstour, 2012 - 2015 Honda Civic, 2013 - 2015 Acura ILX, 2009 - 2014 Acura TSX
Check if this fits your vehicle
Item LocatedUnited States
Quantity4
MaterialIridium + Platinum
Part interchange
5787, ILZKR7B11S
item #10052AX7
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6 Pack Iridium Spark Plug | A-Premium APSP220
A-Premium®Part # APSP220
6 Pack Iridium Spark Plug | A-Premium APSP220
4.7272 Reviews
$36.99
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2-year warranty
90 days free return
Fits 2011 - 2016 BMW 535i xDrive, 2014 - 2017 BMW 640i xDrive Gran Coupe, 2013 - 2014 BMW 740i, 2018 - 2019 BMW 640i xDrive Gran Coupe, 2014 - 2019 BMW X6, 2015 - 2015 BMW 740i, 2015 - 2016 BMW 435i xDrive Gran Coupe, 2014 - 2016 BMW 435i, 2011 - 2013 BMW 135i, 2015 - 2018 BMW M3, 2013 - 2017 BMW X3, 2018 - 2018 BMW 640i xDrive, 2011 - 2013 BMW X5, 2014 - 2016 BMW M235i, 2015 - 2015 BMW ActiveHybrid 7, 2014 - 2016 BMW 435i xDrive, 2016 - 2016 BMW M2, 2017 - 2018 BMW M2, 2013 - 2014 BMW ActiveHybrid 7, 2014 - 2016 BMW 335i GT xDrive
Check if this fits your vehicle
Item LocatedUnited States
Quantity6
MaterialIridium + Platinum
Part interchange
97506, SILZKBR8D8S, 12120039664, 12120040573, 12127622445
item #100522N5
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6 Pack Iridium Spark Plug | A-Premium APSP101
A-Premium®Part # APSP101
6 Pack Iridium Spark Plug | A-Premium APSP101
4.7272 Reviews
$35.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2000 - 2005 Chevrolet Impala, 1994 - 1996 Buick Regal, 2006 - 2009 Ford Fusion, 2005 - 2009 Buick Allure, 2001 - 2006 Mazda Tribute, 1997 - 2003 Chevrolet Malibu, 2005 - 2009 Chevrolet Equinox, 2011 - 2013 Chevrolet Silverado 1500, 1995 - 1999 Chevrolet Monte Carlo, 2003 - 2005 GMC Jimmy, 1999 - 2013 GMC Sierra 1500, 1994 - 2003 Pontiac Grand Prix, 1995 - 2002 Pontiac Firebird, 2005 - 2006 Pontiac G6, 1994 - 2005 Buick Century, 1997 - 2008 Pontiac Grand Prix, 1994 - 1998 Pontiac Grand Am, 1996 - 2005 Chevrolet Astro, 1996 - 2005 Mercury Sable, 2006 - 2008 Buick Lucerne
Check if this fits your vehicle
Item LocatedUnited States
Quantity6
MaterialIridium + Platinum
Part interchange
7164, TR55IX, 3951, TR55, 3403, TR55GP
item #10051LH0
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8 Pack Iridium Spark Plug | A-Premium APSP048
A-Premium®Part # APSP048
8 Pack Iridium Spark Plug | A-Premium APSP048
4.7272 Reviews
$45.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2009 - 2020 Chrysler 300, 2008 - 2009 Chrysler Aspen, 2009 - 2009 Chrysler Aspen, 2009 - 2020 Dodge Challenger, 2009 - 2020 Dodge Charger, 2008 - 2010 Dodge Dakota, 2008 - 2009 Dodge Durango, 2011 - 2020 Dodge Durango, 2009 - 2009 Dodge Durango, 2009 - 2010 Dodge Ram 1500, 2008 - 2010 Dodge Ram 1500, 2009 - 2010 Dodge Ram 2500, 2009 - 2009 Dodge Ram 3500, 2011 - 2011 Hyundai Equus, 2009 - 2012 Hyundai Genesis, 2003 - 2008 INFINITI FX45, 2003 - 2004 INFINITI M45, 2006 - 2010 INFINITI M45, 2002 - 2006 INFINITI Q45, 2004 - 2010 INFINITI QX56
Check if this fits your vehicle
Item LocatedUnited States
Quantity8
MaterialIridium + Platinum
Part interchange
4469, LFR5AIX11, 5018, LFR5AGP, 92174, LZFR5C11, 92145, LZFR5CI11, 
...View more
item #100523YA
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8 Pack Iridium Spark Plug | A-Premium APSP271
A-Premium®Part # APSP271
8 Pack Iridium Spark Plug | A-Premium APSP271
4.7272 Reviews
$59.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2005 - 2007 Ford Expedition, 2008 - 2008 Ford Expedition, 2004 - 2007 Ford F-150, 2008 - 2008 Ford F-150, 2005 - 2008 Ford F-250 Super Duty, 2007 - 2008 Ford F-350 Super Duty, 2005 - 2006 Ford F-350 Super Duty, 2006 - 2008 Lincoln Mark LT, 2005 - 2008 Lincoln Navigator
Check if this fits your vehicle
Item LocatedUnited States
Quantity8
MaterialIridium + Platinum
Part interchange
SP-546, SP-515, PZK14F, PZH14F, SP507
item #1000PZ4X
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6 Pack Iridium Spark Plug | A-Premium APSP111
A-Premium®Part # APSP111
6 Pack Iridium Spark Plug | A-Premium APSP111
4.7272 Reviews
$39.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2017 - 2020 Acura MDX, 2013 - 2018 Acura RDX, 2009 - 2012 Acura TL, 2010 - 2014 Acura TSX, 2017 - 2020 Chrysler Pacifica, 2020 - 2020 Chrysler Voyager, 2016 - 2020 Dodge Durango, 2008 - 2009 Honda Accord, 2010 - 2017 Honda Accord, 2010 - 2011 Honda Accord Crosstour, 2012 - 2015 Honda Crosstour, 2008 - 2010 Honda Odyssey, 2009 - 2011 Honda Pilot, 2009 - 2014 Honda Ridgeline, 2020 - 2021 Jeep Gladiator, 2016 - 2020 Jeep Grand Cherokee, 2018 - 2020 Jeep Wrangler, 2019 - 2020 Ram 1500
Check if this fits your vehicle
Item LocatedUnited States
Quantity6
MaterialIridium + Platinum
Part interchange
7751, ILZKR7B11
item #100525RE
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8 Pack Iridium Spark Plug | A-Premium APSP090
A-Premium®Part # APSP090
8 Pack Iridium Spark Plug | A-Premium APSP090
4.7272 Reviews
$49.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2017 - 2019 Ford E-350 Super Duty, 2019 - 2019 Ford E-450 Super Duty, 2011 - 2017 Ford F-150, 2010 - 2014 Ford F-150, 2011 - 2021 Ford F-250 Super Duty, 2011 - 2021 Ford F-350 Super Duty, 2011 - 2019 Ford Mustang, 2015 - 2018 Ford Mustang
Check if this fits your vehicle
Item LocatedUnited States
Quantity8
MaterialIridium + Platinum
Part interchange
6509, LTR6IX11, 90198, LTR6GP, 90117, ILTR6E11, 91276, LTR6AHX
item #1005236P
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6 Pack Iridium Spark Plug | A-Premium APSP085
A-Premium®Part # APSP085
6 Pack Iridium Spark Plug | A-Premium APSP085
4.7272 Reviews
$36.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2001 - 2003 Acura CL, 2002 - 2003 Acura TL, 1997 - 1998 Dodge B1500, 1997 - 1997 Dodge B2500, 2004 - 2010 Dodge Dakota, 1997 - 2003 Dodge Dakota, 2004 - 2009 Dodge Durango, 1998 - 1999 Dodge Durango, 2007 - 2011 Dodge Nitro, 2002 - 2010 Dodge Ram 1500, 1997 - 2001 Dodge Ram 1500, 1999 - 2003 Dodge Ram 1500 Van, 2001 - 2001 Dodge Ram 2500 Van, 1993 - 1997 Ford Probe, 2006 - 2010 Jeep Commander, 2005 - 2010 Jeep Grand Cherokee, 2002 - 2012 Jeep Liberty, 2006 - 2009 Mitsubishi Raider, 2011 - 2013 Ram 1500, 2011 - 2011 Ram Dakota
Check if this fits your vehicle
Item LocatedUnited States
Quantity6
MaterialIridium + Platinum
Part interchange
6441, ZFR6FIX11, 7100, ZFR6FGP, 94279, FR6AHXS, 4291, ZFR6F11, 
...View more
item #100529R7
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4 Pack Iridium Spark Plug | A-Premium APSP154
A-Premium®Part # APSP154
4 Pack Iridium Spark Plug | A-Premium APSP154
4.7272 Reviews
$26.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2014 - 2016 Kia Forte, 2014 - 2016 Kia Forte, 2017 - 2018 Kia Forte, 2014 - 2017 Kia Forte Koup, 2014 - 2018 Kia Forte5, 2017 - 2020 Kia Optima, 2016 - 2016 Kia Optima, 2014 - 2017 Kia Rondo, 2016 - 2016 Kia Sorento, 2015 - 2020 Kia Sorento, 2012 - 2019 Kia Soul, 2016 - 2020 Kia Sportage, 2013 - 2015 Acura ILX, 2013 - 2015 Acura ILX, 2009 - 2014 Acura TSX, 2008 - 2012 Honda Accord, 2012 - 2015 Honda Civic, 2012 - 2015 Honda Civic, 2012 - 2015 Honda CR-V, 2012 - 2015 Honda Crosstour
Check if this fits your vehicle
Item LocatedUnited States
Quantity4
MaterialIridium + Platinum
Part interchange
93175, LKR7DIX11S, 97390, LKR7BGPS, 96358, LKR7AHXS, 95710, DILZKR7B11GS
item #100528R1
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6 Pack Iridium Spark Plug | A-Premium APSP192
A-Premium®Part # APSP192
6 Pack Iridium Spark Plug | A-Premium APSP192
4.7272 Reviews
$29.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2010 - 2013 BMW 128i, 2010 - 2011 BMW 323i, 2010 - 2013 BMW 328i, 2010 - 2013 BMW 328i xDrive, 2010 - 2011 BMW 528i, 2010 - 2010 BMW 528i xDrive, 2010 - 2012 BMW X3, 2010 - 2010 BMW X5, 2010 - 2011 BMW Z4
Check if this fits your vehicle
Item LocatedUnited States
Quantity6
MaterialIridium + Platinum
Part interchange
95712, LZFR6AP11GS
item #10051SND
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4 Pack Iridium Spark Plug | A-Premium APSP018
A-Premium®Part # APSP018
4 Pack Iridium Spark Plug | A-Premium APSP018
4.7272 Reviews
$23.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2006 - 2009 Audi A3, 2012 - 2014 Volkswagen GTI, 2015 - 2017 Audi Q3 Quattro, 2009 - 2010 Volkswagen Passat CC, 2007 - 2008 Volkswagen Jetta, 2010 - 2013 Audi A3, 2016 - 2017 Volkswagen CC, 2012 - 2012 Volkswagen Beetle, 2013 - 2015 Volkswagen CC, 2005 - 2016 Audi A4 Quattro, 2009 - 2009 Volkswagen Jetta, 2013 - 2013 Volkswagen Beetle, 2005 - 2016 Audi A4, 2009 - 2015 Audi TT Quattro, 2006 - 2010 Volkswagen Passat, 2011 - 2017 Audi Q5, 2009 - 2009 Audi TT, 2008 - 2008 Audi TT, 2010 - 2017 Audi A5 Quattro, 2010 - 2014 Audi A5
Check if this fits your vehicle
Item LocatedUnited States
Quantity4
MaterialIridium + Platinum
Part interchange
2667, BKR7EIX
item #10051SX3
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6 Pack Iridium Spark Plug | A-Premium APSP177
A-Premium®Part # APSP177
6 Pack Iridium Spark Plug | A-Premium APSP177
4.7272 Reviews
$41.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2015 - 2018 Ford Expedition, 2019 - 2021 Ford Expedition, 2020 - 2020 Ford Explorer, 2019 - 2019 Ford Explorer, 2013 - 2018 Ford Explorer, 2020 - 2021 Ford F-150, 2011 - 2014 Ford F-150, 2019 - 2020 Ford F-150, 2015 - 2017 Ford F-150, 2018 - 2018 Ford F-150, 2019 - 2019 Ford Flex, 2010 - 2018 Ford Flex, 2019 - 2019 Ford Fusion, 2019 - 2019 Ford Police Interceptor Sedan, 2017 - 2018 Ford Police Interceptor Sedan, 2013 - 2018 Ford Police Interceptor Sedan, 2020 - 2020 Ford Police Interceptor Utility, 2020 - 2020 Ford Police Interceptor Utility, 2019 - 2019 Ford Police Interceptor Utility, 2014 - 2018 Ford Police Interceptor Utility
Check if this fits your vehicle
Item LocatedUnited States
Quantity6
MaterialIridium + Platinum
Part interchange
94374, LTR6IX, 94372, LTR6GP8, 90495, LTR6BHX
item #100522CY
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4 Pack Iridium Spark Plug | A-Premium APSP149
A-Premium®Part # APSP149
4 Pack Iridium Spark Plug | A-Premium APSP149
4.7272 Reviews
$23.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2012 - 2019 Hyundai Accent, 2011 - 2011 Hyundai Elantra, 2012 - 2017 Hyundai Veloster, 2012 - 2019 Kia Rio, 2012 - 2019 Kia Soul
Check if this fits your vehicle
Item LocatedUnited States
Quantity4
MaterialIridium + Platinum
Part interchange
92873, LZKR6AIX
item #10051U12
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4 Pack Iridium Spark Plug | A-Premium APSP081
A-Premium®Part # APSP081
4 Pack Iridium Spark Plug | A-Premium APSP081
4.7272 Reviews
$28.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2003 - 2005 Dodge SX 2.0, 2003 - 2005 Volkswagen Beetle, 1995 - 1998 Suzuki Sidekick, 2000 - 2000 Audi A4 Quattro, 2003 - 2003 Saab 9-3, 1995 - 1998 Mitsubishi Eclipse, 2004 - 2004 Chevrolet Optra, 1996 - 1999 BMW 318is, 2008 - 2010 Mitsubishi Lancer, 1999 - 2001 Volkswagen Beetle, 2002 - 2006 Mini Cooper, 2001 - 2005 Audi A4 Quattro, 2000 - 2004 Kia Spectra, 1996 - 1999 BMW 318i, 1997 - 1999 Audi A4 Quattro, 1990 - 1991 Volkswagen Passat, 1991 - 1991 Isuzu Impulse, 2002 - 2002 Volkswagen Beetle, 1995 - 2000 Suzuki Esteem, 1998 - 2001 Kia Sephia
Check if this fits your vehicle
Item LocatedUnited States
Quantity4
MaterialIridium + Platinum
Part interchange
6418, BKR6EIX, 6458, PFR6Q
item #100529AU
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4 Pack Iridium Spark Plug | A-Premium APSP159
A-Premium®Part # APSP159
4 Pack Iridium Spark Plug | A-Premium APSP159
4.7272 Reviews
$26.99
Edit ZIP code
2-year warranty
90 days free return
Fits 2016 - 2020 Acura ILX, 2015 - 2020 Acura TLX, 2014 - 2015 Honda Accord, 2013 - 2017 Honda Accord, 2017 - 2017 Honda Accord, 2016 - 2016 Honda Civic, 2017 - 2020 Honda Civic, 2015 - 2019 Honda CR-V, 2015 - 2019 Honda Fit, 2011 - 2015 Lexus CT200h, 2014 - 2019 Mazda 3, 2012 - 2013 Mazda 3, 2014 - 2020 Mazda 3, 2014 - 2020 Mazda 3 Sport, 2011 - 2013 Mazda 3 Sport, 2014 - 2020 Mazda 3 Sport, 2014 - 2017 Mazda 6, 2018 - 2020 Mazda 6, 2016 - 2020 Mazda CX-3, 2020 - 2020 Mazda CX-30
Check if this fits your vehicle
Item LocatedUnited States
Quantity4
MaterialIridium + Platinum
Part interchange
93501, LKAR7BIX11S, 92649, LKAR7BGPS, 92274, LKAR7AHXS, 96964, DILKAR7H11GS
item #10052GVW
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Page 2 of 46

Choose Spark Plugs for the Exact Engine

A spark plug creates the ignition spark inside a gasoline engine's combustion chamber. Start a spark plug replacement with the exact year, make, model, trim, and engine, then verify the listed plug number, set quantity, thread and seat design, reach, heat range, gap specification, and hex size. A plug that threads into the head is not necessarily correct for the engine or ignition system.

Compare Plug Designs and Set Quantities

Current A-Premium listings include iridium-plus-platinum and double-iridium designs in four-, six-, and eight-piece sets. Quantity should match the application, not simply the cylinder count; some engines use more than one plug per cylinder, and the product note may identify that arrangement. Confirm every included plug shares the required part specification.

Performance labels do not replace fitment data

High performance spark plugs are not automatically a better choice for every engine. Electrode material, projected tip, resistor design, heat range, thread reach, and gap must suit the ignition and combustion design. Use the vehicle manufacturer's specified plug or a documented cross-reference rather than selecting by material alone.

Understand Spark Plug Socket Size and Fitment

Spark plug socket size describes the hex that the installation tool grips. A 14 mm or 16 mm spark-plug socket identifies only the plug's hex size; it does not confirm thread diameter, reach, seat type, or engine compatibility. Verify the plug's specification and the tool clearance in the cylinder-head well before service. Well depth and surrounding components can also affect the extension and socket design needed to remove the plug without damaging nearby parts.

Compare the listing's interchange number with the vehicle information and service manual. Do not assume that two plugs with the same socket size share the same gap or heat range. If a product arrives with a preset gap, confirm whether the vehicle or plug manufacturer permits adjustment before touching the electrodes.

Check Misfires Before Blaming the Spark Plugs

A misfire, rough idle, hard start, weak acceleration, increased fuel use, or a warning light can justify inspection, but these symptoms do not prove the spark plugs are the cause. Read diagnostic codes and inspect plug condition, coil or wire connections, air and fuel delivery, and mechanical condition before ordering parts.

On engines that use them, damaged spark plug wires can interrupt ignition voltage. Mixture problems or a leaking fuel injector can also foul a plug or create a similar drivability complaint. Correct the underlying fault so new plugs are not exposed to the same condition.

Install Spark Plugs with Vehicle-Specific Procedures

Work on a cool engine, clear debris from the plug wells, and start each plug by hand to reduce cross-threading risk. Use the vehicle service information for removal steps, gap, thread treatment, and tightening torque; do not apply one value to every plug or cylinder head. Fine-wire iridium electrodes can be damaged by careless adjustment, so follow the selected plug manufacturer's instructions before changing a preset gap. Reconnect coils or wires securely, then confirm smooth operation and recheck any diagnostic codes.

Frequently Asked Questions (FAQ)

How often should spark plugs be replaced?

Follow the vehicle's maintenance schedule because intervals depend on the engine and specified plug. Inspect sooner when diagnosis finds misfires, damaged electrodes, heavy deposits, or another plug-related condition.

How do I find the correct spark plug socket size?

Check the specified plug's hex dimension and the service information for your engine. The socket must fit the hex and reach the plug well without contacting surrounding components.

Should I change the gap on a new iridium spark plug?

Only if the vehicle and plug instructions call for it. Many iridium plugs arrive preset, and careless adjustment can damage the fine electrode, so verify the required gap first.

Will high performance spark plugs add power to any car?

No universal power gain should be expected. Correct heat range, dimensions, gap, and ignition compatibility matter more than a performance label. Choose the specification required for the engine.

Should all spark plugs be replaced as a set?

For scheduled service, replacing the complete specified set helps keep plug type and wear consistent. If one plug is damaged by another fault, diagnose that cylinder and inspect the remaining plugs before deciding.

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Aug 10, 2026

P0306 Code: Cylinder 6 Misfire Causes, Diagnosis, and Fix

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Aug 10, 2026

Why Does Only One Spark Plug Look Bad? Diagnose That Cylinder Before Replacing Parts

A bad spark plug doesn't mean total failure. Avoid guesswork by diagnosing the cylinder first. Learn to read plug conditions, run a coil-swap test, and pinpoint if it's a bad coil, injector, or compression. Replace only the exact parts confirmed.

Aug 07, 2026

P0302 Code: How to Diagnose and Fix a Cylinder 2 Misfire

The P0302 diagnostic trouble code indicates a misfire condition in cylinder 2 of the engine. Specifically, the P0302 code is triggered when the engine control module (ECM) detects that cylinder 2 is not firing properly or is experiencing a misfire.

Jul 30, 2026

What Does It Sound Like When a Spark Plug Goes Bad?

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