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Subaru Spark Plug

75 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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Spark Plug - Denso 4704Spark Plug - Denso 4704
DensoPart # 4704
Spark Plug - Denso 4704
44 Reviews
$20.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2013-2015 Acura ILX, 2006-2006 BMW 325i, 2006-2006 BMW 325xi, 2006-2006 BMW 330i, 2006-2006 BMW 330xi, 2006-2006 BMW Z4, 2006-2006 BMW Z4, 2006-2006 BMW Z4, 2006-2007 BMW 525i, 2006-2007 BMW 525xi, 2006-2007 BMW 530i, 2006-2007 BMW 530xi, 2007-2008 BMW 328xi, 2007-2008 BMW X5, 2007-2008 BMW Z4, 2007-2010 BMW X3, 2007-2011 BMW 328i, 2008-2008 BMW 528xi, 2008-2011 BMW 528i, 2008-2013 BMW 128i
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
4704, 22401 AA630, 22401 AA580, 32 01 0632, 22401 AA751, 22401 AA761, 22401 AA670, 22401 AA750, 
...View more
item #1002HKC9
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Spark Plug - Denso 3457
DensoPart # 3457
Spark Plug - Denso 3457
44 Reviews
$28.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2008-2013 INFINITI G37, 2011-2013 INFINITI M37, 2013-2013 INFINITI EX37, 2013-2013 INFINITI FX37, 2014-2015 INFINITI Q50, 2014-2015 INFINITI Q60, 2014-2017 INFINITI QX50, 2014-2017 INFINITI QX70, 2014-2019 INFINITI Q70, 2015-2015 INFINITI Q40, 2015-2019 INFINITI Q70L, 2017-2018 INFINITI Q60, 2017-2021 INFINITI Q50, 2019-2022 INFINITI Q60, 2022-2022 INFINITI Q50, 2011-2013 Mercedes-Benz SLS AMG, 2014-2014 Mercedes-Benz SLS AMG, 2015-2015 Mercedes-Benz SLS AMG, 2009-2020 Nissan 370Z, 2009-2021 Nissan GT-R
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
3457, FXE24HR11, 22401 AA830, 22401-JK01D, 22401-JF01D, 22401-5CA1D, 159 159 00 03, 12 12 0 039 664, 
...View more
item #1002HEHD
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Bosch 9607 Spark Plug
BoschPart # 9607
Bosch 9607 Spark Plug
54 Reviews
$17.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1986-1989 Acura Integra, 1986-1990 Acura Legend, 1990-1991 Acura Integra, 1991-1992 Acura Legend, 1991-1994 Acura NSX, 1992-1993 Acura Integra, 1992-1994 Acura Vigor, 1993-1995 Acura Legend, 1994-2001 Acura Integra, 1995-1995 Acura TL, 1995-2005 Acura NSX, 1996-1998 Acura TL, 1996-1999 Acura SLX, 1997-2001 Acura Integra, 1990-1992 Chevrolet Corvette, 1993-1994 Chevrolet Beretta, 1998-1998 Chevrolet Tracker, 1998-1999 Chevrolet Metro, 1999-1999 Chevrolet Tracker, 1999-1999 Chevrolet Tracker
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
9607
item #1002A7V5
Show less
Bosch 9603 Spark Plug
BoschPart # 9603
Bosch 9603 Spark Plug
54 Reviews
$17.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1991-1992 Acura Legend, 1991-1994 Acura NSX, 1992-1993 Acura Integra, 1993-1995 Acura Legend, 1994-1996 Acura Integra, 1995-2005 Acura NSX, 1997-1998 Acura Integra, 1997-1998 Acura Integra, 1999-1999 Acura Integra, 1999-1999 Acura Integra, 2000-2001 Acura Integra, 2000-2001 Acura Integra, 2006-2006 Chrysler Crossfire, 2002-2005 Ford Thunderbird, 2011-2016 Honda CR-Z, 1998-2001 Jaguar XJR, 2000-2002 Jaguar XKR, 2001-2001 Jaguar Vanden Plas, 2001-2001 Jaguar XJ8, 1990-1994 Lexus LS400
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
9603
item #1002A5UV
Show less
Denso 3145 Spark Plug
DensoPart # 3145
Denso 3145 Spark Plug
44 Reviews
$7.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1992-1994 Audi S4, 1995-1997 Audi S6, 2000-2000 Audi A4 Quattro, 2000-2000 Audi TT Quattro, 2001-2003 Audi TT Quattro, 2001-2006 Audi TT, 2002-2002 Audi A4 Quattro, 2003-2004 Audi A6 Quattro, 2003-2005 Audi A4 Quattro, 2003-2005 Audi Allroad Quattro, 2003-2006 Audi A4, 2004-2006 Audi TT Quattro, 2005-2009 Audi A4, 2005-2009 Audi A4 Quattro, 2014-2016 Cadillac ELR, 2013-2015 Chevrolet Cruze, 2013-2015 Chevrolet Volt, 2013-2017 Chevrolet Sonic, 2016-2016 Chevrolet Cruze Limited, 2000-2000 Chrysler Cirrus
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
3145, 3300 3862, K20PR-U, 91171719, 09482-00427, 91173854, 09482-00429, 19302724, 
...View more
item #1002H98U
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Denso 3245 Spark Plug
DensoPart # 3245
Denso 3245 Spark Plug
44 Reviews
$17.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1992-1993 Audi 100, 1992-1994 Audi S4, 1993-1995 Audi 90, 1993-1995 Audi 90 Quattro, 1995-1997 Audi S6, 2000-2000 Audi A4 Quattro, 2000-2003 Audi TT Quattro, 2001-2006 Audi TT, 2003-2004 Audi A6 Quattro, 2003-2005 Audi A4 Quattro, 2003-2005 Audi Allroad Quattro, 2003-2006 Audi A4, 2004-2006 Audi TT Quattro, 2005-2009 Audi A4, 2005-2009 Audi A4 Quattro, 2014-2016 Cadillac ELR, 2013-2015 Chevrolet Cruze, 2013-2015 Chevrolet Volt, 2013-2017 Chevrolet Sonic, 2016-2016 Chevrolet Cruze Limited
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
3245, 22401 AA531, 22401 AA530, 32 00 9439, PK20PR-P8, 96068562, 96068563, 91171719, 
...View more
item #1002HA94
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Denso 3264 Spark Plug
DensoPart # 3264
Denso 3264 Spark Plug
44 Reviews
$12.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1991-1995 Acura Legend, 1997-1997 Acura SLX, 1984-1984 Bentley Corniche, 1984-1986 Bentley Mulsanne, 1986-1986 Bentley Continental, 1987-1991 Bentley Eight, 1988-1991 Bentley Continental, 1988-1992 Bentley Mulsanne, 1989-1997 Bentley Turbo R, 1993-1996 Bentley Continental, 1993-1997 Bentley Brooklands, 1996-1997 Bentley Azure, 1999-1999 Bentley Azure, 1999-2001 Bentley Continental, 2000-2001 Bentley Azure, 1995-1995 Chrysler Sebring, 1995-1997 Chrysler Cirrus, 1996-1998 Chrysler Sebring, 1999-1999 Chrysler Sebring, 2000-2000 Chrysler Cirrus
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
3264, 22401 AA65A, 32 00 5952, 22401 AA650, PK16PR11, 22401-50Y05, AGSP32FP, 22401-7B004, 
...View more
item #1002H73R
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Bosch 8100 Spark Plug
BoschPart # 8100
Bosch 8100 Spark Plug
54 Reviews
$12.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1990-1991 Acura Integra, 1991-1995 Acura Legend, 1996-1998 Acura TL, 1996-2004 Acura RL, 1996-1996 BMW M3, 1997-1999 BMW M3, 1998-2000 BMW Z3, 1994-1998 Bentley Brooklands, 1996-1998 Bentley Azure, 2000-2001 Bentley Arnage, 2000-2001 Bentley Azure, 1985-1985 Buick Riviera, 1985-1989 Buick Electra, 1985-1990 Buick LeSabre, 1986-1987 Buick Regal, 1988-1994 Buick Skylark, 1986-1986 Cadillac Fleetwood, 1987-1989 Cadillac Brougham, 1990-1990 Cadillac Brougham, 1997-2001 Cadillac Catera
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
8100
item #1002AAV8
Show less
Bosch 6702 Spark Plug
BoschPart # 6702
Bosch 6702 Spark Plug
54 Reviews
$12.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1990-1991 Acura Integra, 1991-1995 Acura Legend, 1996-1998 Acura TL, 1996-2004 Acura RL, 1996-1996 BMW M3, 1997-1999 BMW M3, 1998-2000 BMW Z3, 1997-2001 Cadillac Catera, 2003-2003 Cadillac CTS, 2004-2004 Cadillac CTS, 2000-2000 Chevrolet Tracker, 2000-2000 Chevrolet Tracker, 2000-2002 Chevrolet Prizm, 2001-2002 Chevrolet Tracker, 2001-2002 Chevrolet Tracker, 2003-2003 Chevrolet Tracker, 2004-2004 Chevrolet Tracker, 1995-1996 Chrysler Cirrus, 1995-1997 Chrysler Cirrus, 1995-1999 Chrysler Sebring
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
6702
item #1002A6AY
Show less
Denso 3168 Spark Plug
DensoPart # 3168
Denso 3168 Spark Plug
44 Reviews
$15.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1993-1993 Chevrolet Beretta, 1999-1999 Chevrolet Tracker, 1999-1999 Chevrolet Tracker, 1999-2000 Chevrolet Tracker, 2000-2000 Chevrolet Metro, 2001-2001 Chevrolet Metro, 2004-2008 Chevrolet Aveo, 2007-2008 Chevrolet Aveo5, 1995-1999 Chrysler Cirrus, 1996-1998 Chrysler Sebring, 1996-1999 Chrysler Sebring, 2001-2003 Chrysler Sebring, 1999-2002 Daewoo Lanos, 1999-2002 Daewoo Nubira, 1989-1992 Daihatsu Charade, 1990-1992 Daihatsu Rocky, 1995-1998 Dodge Avenger, 1995-1999 Dodge Avenger, 1995-1999 Dodge Stratus, 1996-1996 Dodge Avenger
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
3168, 22401 AA310, 22401 AA540, 22401 AA550, 22401 AA65A, 22401 AA450, 22401 AA370, PK20PR11, 
...View more
item #1002H6U8
Show less
Bosch 8122 Spark Plug
BoschPart # 8122
Bosch 8122 Spark Plug
54 Reviews
$12.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2001-2003 INFINITI QX4, 2002-2004 INFINITI I35, 2002-2005 INFINITI Q45, 2003-2004 INFINITI M45, 2003-2005 INFINITI FX45, 2003-2007 INFINITI G35, 2003-2008 INFINITI FX35, 2004-2006 INFINITI QX56, 2006-2006 INFINITI Q45, 2006-2008 INFINITI M35, 2006-2010 INFINITI M45, 2007-2008 INFINITI FX45, 2008-2011 Lexus LX570, 2010-2023 Lexus GX460, 2013-2021 Lexus LX570, 2000-2001 Nissan Sentra, 2001-2007 Nissan Pathfinder, 2002-2006 Nissan Altima, 2002-2006 Nissan Maxima, 2002-2006 Nissan Sentra
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
8122
item #1002A96S
Show less
Spark Plug - Denso 3062
DensoPart # 3062
Spark Plug - Denso 3062
44 Reviews
$10.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1963-1967 MG MGB, 1972-1974 Nissan 620 Pickup, 1973-1973 Nissan 610, 1974-1974 Nissan 710, 1974-1975 Subaru DL, 1976-1976 Subaru DL, 1979-1979 Subaru DL
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
3062, W20EX-U
item #1002HAS2
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Bosch 8101 Spark Plug
BoschPart # 8101
Bosch 8101 Spark Plug
54 Reviews
$12.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1986-1990 Acura Legend, 1990-1991 Acura Integra, 1991-1992 Acura Legend, 1991-1994 Acura NSX, 1992-1993 Acura Integra, 1992-1994 Acura Vigor, 1993-1995 Acura Legend, 1994-2001 Acura Integra, 1995-1995 Acura TL, 1995-2005 Acura NSX, 1996-1998 Acura TL, 1996-1999 Acura SLX, 1997-2001 Acura Integra, 1990-1991 Chevrolet Corvette, 1990-1991 Chevrolet Corvette, 1992-1992 Chevrolet Corvette, 1993-1994 Chevrolet Beretta, 1998-1998 Chevrolet Tracker, 1998-1999 Chevrolet Metro, 1999-1999 Chevrolet Tracker
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
8101
item #1002A6XA
Show less
Denso 4702 Spark Plug
DensoPart # 4702
Denso 4702 Spark Plug
44 Reviews
$14.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1992-1992 Acura NSX, 1992-1993 Acura Integra, 1994-2001 Acura Integra, 1994-2005 Acura NSX, 1996-1996 Acura SLX, 1997-1998 Acura Integra, 1997-2005 Acura EL, 2000-2001 Acura Integra, 2002-2006 Acura RSX, 2004-2008 Acura TL, 2004-2008 Acura TSX, 2005-2008 Acura RL, 2007-2009 Acura MDX, 1994-1995 Alfa Romeo 164, 1990-1991 Audi Coupe Quattro, 1992-1994 Audi 100, 1992-1994 Audi 100 Quattro, 1992-1994 Audi S4, 1993-1995 Audi 90, 1993-1995 Audi 90 Quattro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
4702, 22401 AA370, 22401 AA550, 22401 AA731, 22401 AA450, 22401 AA540, 22401 AA730, 22401 AA531, 
...View more
item #1002HKPE
Show less
Bosch 6724 Spark Plug
BoschPart # 6724
Bosch 6724 Spark Plug
54 Reviews
$11.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1986-1990 Acura Legend, 1990-1991 Acura Integra, 1991-1992 Acura Legend, 1991-1994 Acura NSX, 1992-1993 Acura Integra, 1992-1994 Acura Vigor, 1993-1995 Acura Legend, 1994-2001 Acura Integra, 1995-1995 Acura TL, 1995-2005 Acura NSX, 1996-1998 Acura TL, 1996-1999 Acura SLX, 1997-2001 Acura Integra, 2000-2004 Audi A8 Quattro, 2000-2006 Audi A6 Quattro, 2001-2003 Audi S8, 2003-2005 Audi Allroad Quattro, 2004-2009 Audi S4, 2005-2006 Audi A8 Quattro, 2008-2008 Audi S5
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
6724
item #1002A5LU
Show less
Denso 3442 Spark Plug
DensoPart # 3442
Denso 3442 Spark Plug
44 Reviews
$25.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2007-2008 INFINITI G35, 2008-2012 INFINITI EX35, 2009-2010 INFINITI M35, 2009-2012 INFINITI FX35, 2009-2013 INFINITI FX50, 2011-2012 INFINITI G25, 2011-2013 INFINITI M56, 2011-2013 INFINITI QX56, 2012-2013 INFINITI M35h, 2013-2013 INFINITI JX35, 2014-2014 INFINITI QX70, 2014-2018 INFINITI Q50, 2014-2018 INFINITI Q70, 2014-2019 INFINITI Q70, 2014-2020 INFINITI QX60, 2014-2021 INFINITI QX80, 2015-2019 INFINITI Q70L, 2012-2012 Jaguar XF, 2012-2012 Jaguar XFR, 2012-2012 Jaguar XJ
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
3442, 22401AA940, 22401 AA780, 22401 AA781, 22401 AA820, 22401 AA95A, 22401AA95A, 22401 AA940, 
...View more
item #1002HCYK
Show less
Denso 3130 Spark Plug
DensoPart # 3130
Denso 3130 Spark Plug
44 Reviews
$7.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1991-1995 Acura Legend, 1997-1997 Acura SLX, 1988-1993 Buick Skylark, 1990-1990 Buick LeSabre, 1986-1989 Chevrolet Corvette, 1987-1992 Chevrolet Camaro, 1990-1992 Chevrolet Beretta, 1995-1995 Chrysler Sebring, 1995-1997 Chrysler Cirrus, 1996-1998 Chrysler Sebring, 1999-1999 Chrysler Sebring, 2000-2000 Chrysler Cirrus, 2000-2000 Chrysler Sebring, 2001-2003 Chrysler Sebring, 2001-2004 Chrysler Sebring, 2001-2004 Chrysler Sebring, 2004-2004 Chrysler Crossfire, 2004-2005 Chrysler Sebring, 2004-2005 Chrysler Sebring, 2004-2005 Chrysler Sebring
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
3130, K16PR-U11, AGSP32C, 22401-50Y05, 22401-5M075, 22401-85E15, 22401-85E14, 22401-50Y04, 
...View more
item #1002H924
Show less
Denso 4701 Spark Plug
DensoPart # 4701
Denso 4701 Spark Plug
44 Reviews
$14.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1991-1995 Acura Legend, 1992-1993 Acura Integra, 1992-1994 Acura Vigor, 1994-1998 Acura Integra, 1994-2001 Acura Integra, 1995-1996 Acura Integra, 1995-2003 Acura TL, 1996-2004 Acura RL, 1997-1999 Acura CL, 1997-1999 Acura SLX, 1997-2001 Acura Integra, 2001-2003 Acura CL, 2001-2006 Acura MDX, 2008-2009 Audi A5 Quattro, 2009-2009 Audi A4 Quattro, 2009-2010 Audi A6, 2010-2010 Audi A5 Quattro, 2011-2011 Audi A6, 1995-1997 BMW 850Ci, 1995-1998 BMW 750iL
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
4701, 22401 AA65A, 22401 AA570, 22401 AA650, 32 00 5952, IK16TT, 19302724, 09482-00549, 
...View more
item #1002HCTR
Show less
Bosch 9683 Spark Plug
BoschPart # 9683
Bosch 9683 Spark Plug
54 Reviews
$27.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2011-2013 Mazda 3 Sport, 2012-2013 Mazda 3, 2012-2013 Mazda 3, 2013-2016 Mazda CX-5, 2014-2017 Mazda 6, 2014-2019 Mazda 3, 2014-2019 Mazda 3 Sport, 2016-2021 Mazda CX-3, 2016-2023 Mazda MX-5 Miata, 2017-2018 Mazda CX-5, 2018-2019 Mazda 6, 2018-2019 Mazda 6, 2018-2019 Mazda 6, 2018-2020 Mazda 6, 2018-2021 Mazda 6, 2018-2021 Mazda 6, 2018-2021 Mazda 6, 2019-2021 Mazda CX-5, 2019-2021 Mazda CX-5, 2019-2021 Mazda CX-5
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
9683
item #1002APLL
Show less
Spark Plug - Denso 3381
DensoPart # 3381
Spark Plug - Denso 3381
44 Reviews
$17.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2006-2006 BMW 325i, 2006-2006 BMW 325xi, 2006-2006 BMW 330i, 2006-2006 BMW 330xi, 2006-2006 BMW Z4, 2006-2006 BMW Z4, 2006-2006 BMW Z4, 2006-2007 BMW 525i, 2006-2007 BMW 525xi, 2006-2007 BMW 530i, 2006-2007 BMW 530xi, 2007-2008 BMW 328xi, 2007-2008 BMW X5, 2007-2008 BMW Z4, 2007-2010 BMW X3, 2007-2011 BMW 328i, 2008-2008 BMW 528xi, 2008-2011 BMW 528i, 2008-2013 BMW 128i, 2009-2009 BMW X5
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Subaru
Item LocatedUnited States
Quantity1
Part interchange
3381, K20HR-U11, 90919-01235, SPFR8TE2AA, 5149 050AB, 5149 888AA, SPFR8TI332, 30650843-0
item #1002HGXU
Show less
Page 2 of 4

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 25, 2026

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Aug 17, 2026

P0301 Code: Cylinder 1 Misfire 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