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Toyota 4Runner Spark Plug

66 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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Bosch 6702 Spark PlugBosch 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: Toyota 4Runner
Item LocatedUnited States
Quantity1
Part interchange
6702
item #1002A6AY
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Denso 6076 Spark Plug
DensoPart # 6076
Denso 6076 Spark Plug
44 Reviews
$10.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2010-2010 Chrysler 300, 2015-2016 Chrysler 200, 2009-2010 Dodge Challenger, 2009-2010 Dodge Ram 1500, 2010-2010 Dodge Charger, 2015-2015 Dodge Challenger, 2015-2015 Dodge Charger, 2015-2016 Dodge Dart, 2015-2016 Dodge Dart, 2016-2017 Fiat 500X, 2007-2008 Hyundai Santa Fe, 2009-2009 Hyundai Santa Fe, 2001-2003 INFINITI QX4, 2002-2004 INFINITI I35, 2002-2006 INFINITI Q45, 2003-2004 INFINITI M45, 2003-2007 INFINITI FX45, 2003-2007 INFINITI G35, 2004-2004 INFINITI QX56, 2004-2007 INFINITI FX35
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota 4Runner
Item LocatedUnited States
Quantity1
Part interchange
6076, K16HPR-U11
item #1004Z3YQ
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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: Toyota 4Runner
Item LocatedUnited States
Quantity1
Part interchange
8122
item #1002A96S
Show less
Denso 3194 Spark Plug
DensoPart # 3194
Denso 3194 Spark Plug
44 Reviews
$12.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1998-2000 Lexus GS300, 1998-2000 Lexus SC300, 1995-1998 Toyota T100, 1995-1999 Toyota Tercel, 1995-2004 Toyota Tacoma, 1996-1999 Toyota Paseo, 1996-2000 Toyota 4Runner, 1998-1999 Toyota Corolla, 2000-2000 Toyota Sienna, 2000-2004 Toyota Tundra, 2001-2002 Toyota 4Runner
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota 4Runner
Item LocatedUnited States
Quantity1
Part interchange
3194, K16TR11, 90919-01192, 94856823, 94859009
item #1002H95Z
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Bosch 8110 Spark Plug
BoschPart # 8110
Bosch 8110 Spark Plug
54 Reviews
$12.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2007-2009 Hyundai Santa Fe, 2001-2003 INFINITI QX4, 2002-2004 INFINITI I35, 2002-2005 INFINITI Q45, 2003-2004 INFINITI M45, 2003-2007 INFINITI G35, 2003-2008 INFINITI FX35, 2003-2008 INFINITI FX45, 2004-2006 INFINITI QX56, 2006-2006 INFINITI Q45, 2006-2008 INFINITI M35, 2006-2010 INFINITI M45, 2006-2010 Kia Optima, 2007-2010 Kia Magentis, 2007-2010 Kia Rondo, 2012-2012 Kia Rondo, 2000-2001 Nissan Sentra, 2001-2007 Nissan Pathfinder, 2002-2006 Nissan Altima, 2002-2006 Nissan Maxima
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota 4Runner
Item LocatedUnited States
Quantity1
Part interchange
8110
item #1002A8WR
Show less
Denso 4708 Spark Plug
DensoPart # 4708
Denso 4708 Spark Plug
44 Reviews
$16.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1959-1961 American Motors Rebel, 1964-1966 American Motors American, 1964-1966 American Motors Classic, 1965-1965 American Motors Classic, 1965-1966 American Motors Ambassador, 1965-1966 American Motors Marlin, 1966-1966 American Motors Ambassador, 1966-1966 American Motors Ambassador, 1966-1966 American Motors American, 1966-1966 American Motors Marlin, 1967-1967 American Motors Ambassador, 1967-1967 American Motors American, 1967-1967 American Motors Marlin, 1967-1967 American Motors Rebel, 1967-1967 American Motors Rebel, 1967-1967 American Motors Rebel, 1967-1967 American Motors Rebel, 1967-1968 American Motors Rebel, 1967-1970 American Motors Rebel, 1968-1968 American Motors American
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota 4Runner
Item LocatedUnited States
Quantity1
Part interchange
4708, IW16TT, 09482-00155, 09482-00167, 09482-00506, 91171720, 96057875, 98079-551-83, 
...View more
item #1002HER3
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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: Toyota 4Runner
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: Toyota 4Runner
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
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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: Toyota 4Runner
Item LocatedUnited States
Quantity1
Part interchange
6724
item #1002A5LU
Show less
Denso 3134 Spark Plug
DensoPart # 3134
Denso 3134 Spark Plug
44 Reviews
$12.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2008-2009 Audi A5 Quattro, 2009-2009 Audi A4 Quattro, 2010-2010 Audi A5 Quattro, 2000-2002 Chevrolet Prizm, 2000-2000 Chrysler Cirrus, 2000-2000 Chrysler Voyager, 1999-1999 Dodge Avenger, 1999-2000 Dodge Caravan, 2000-2000 Dodge Avenger, 2000-2000 Dodge Stratus, 2007-2007 Dodge Ram 1500, 2008-2008 Dodge Dakota, 2006-2009 Hyundai Sonata, 2003-2007 Jaguar S-Type, 2004-2007 Jaguar Vanden Plas, 2004-2007 Jaguar XJ8, 2004-2007 Jaguar XJR, 2005-2006 Jaguar XK8, 2005-2007 Jaguar Super V8, 2005-2007 Jaguar XKR
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota 4Runner
Item LocatedUnited States
Quantity1
Part interchange
3134, PK16R11, 90919-01168, 90919-01168-83, 90919-01164, 90080-91184, 90919-01169, 90919-01166, 
...View more
item #1002H5XR
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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: Toyota 4Runner
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
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: Toyota 4Runner
Item LocatedUnited States
Quantity1
Part interchange
3381, K20HR-U11, 90919-01235, SPFR8TE2AA, 5149 050AB, 5149 888AA, SPFR8TI332, 30650843-0
item #1002HGXU
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Spark Plug - Bosch 79176
BoschPart # 79176
Spark Plug - Bosch 79176
54 Reviews
$10.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2003-2009 Toyota 4Runner, 2005-2010 Toyota Tundra, 2005-2015 Toyota Tacoma, 2007-2009 Toyota FJ Cruiser, 2011-2011 Toyota Tundra
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota 4Runner
Item LocatedUnited States
Quantity1
Part interchange
79176
item #1002A833
Show less
Denso 4706 Spark Plug
DensoPart # 4706
Denso 4706 Spark Plug
44 Reviews
$14.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1990-1991 Acura Integra, 1988-1994 BMW 750iL, 1991-1992 BMW 850i, 1993-1994 BMW 850Ci, 1994-1995 BMW 850CSi, 1985-1985 Buick Riviera, 1985-1986 Buick LeSabre, 1985-1989 Buick Electra, 1986-1987 Buick Regal, 1988-1989 Buick LeSabre, 1986-1986 Cadillac Fleetwood, 1987-1989 Cadillac Brougham, 1990-1990 Cadillac Brougham, 1986-1986 Chevrolet Caprice, 1986-1990 Chevrolet Caprice, 1987-1987 Chevrolet Caprice, 1988-1988 Chevrolet Nova, 2010-2010 Chrysler Town & Country, 2010-2010 Dodge Journey, 2010-2011 Dodge Nitro
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota 4Runner
Item LocatedUnited States
Quantity1
Part interchange
4706, IQ16TT, 98079-551-4A, 98079-551-58, 98079-551-48, 90919-01129, 94847399, 90919-01152, 
...View more
item #1002HHS0
Show less
Spark Plug - Denso 3421
DensoPart # 3421
Spark Plug - Denso 3421
44 Reviews
$20.99
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 328i, 2007-2010 BMW X3, 2008-2008 BMW 528xi, 2008-2010 BMW 128i, 2008-2011 BMW 528i, 2009-2009 BMW X5
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota 4Runner
Item LocatedUnited States
Quantity1
Part interchange
3421, 32 01 0632, 22401 AA580, SK20HR11, 12293-PHM-A01, 90919-A1002, 90919-01235, 90919-01191, 
...View more
item #1002HDTT
Show less
Denso 3129 Spark Plug
DensoPart # 3129
Denso 3129 Spark Plug
44 Reviews
$8.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1990-1992 Geo Prizm, 1991-1992 Geo Prizm, 1988-1988 Toyota 4Runner, 1988-1988 Toyota Corolla, 1988-1988 Toyota Corolla, 1988-1988 Toyota Corolla, 1988-1988 Toyota Corolla, 1988-1988 Toyota Corolla, 1988-1988 Toyota Corolla, 1988-1988 Toyota Corolla, 1988-1988 Toyota Corolla, 1988-1988 Toyota Pickup, 1989-1989 Toyota Celica, 1990-1990 Toyota Corolla, 1990-1990 Toyota Corolla, 1990-1990 Toyota Corolla, 1990-1990 Toyota Corolla, 1990-1991 Toyota Corolla, 1990-1991 Toyota Corolla, 1990-1993 Toyota Celica
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota 4Runner
Item LocatedUnited States
Quantity1
Part interchange
3129, Q16R-U, 90919-01153, 94847399
item #1002H7HH
Show less
Denso 3004 Spark Plug
DensoPart # 3004
Denso 3004 Spark Plug
44 Reviews
$14.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1959-1961 American Motors Rebel, 1965-1965 American Motors Ambassador, 1965-1965 American Motors American, 1965-1965 American Motors Classic, 1965-1965 American Motors Classic, 1966-1967 American Motors Ambassador, 1966-1967 American Motors Marlin, 1966-1968 American Motors American, 1967-1967 American Motors Ambassador, 1967-1967 American Motors American, 1967-1967 American Motors Marlin, 1967-1967 American Motors Marlin, 1967-1967 American Motors Rebel, 1967-1967 American Motors Rebel, 1967-1967 American Motors Rebel, 1967-1967 American Motors Rebel, 1967-1968 American Motors American, 1967-1968 American Motors Rebel, 1967-1969 American Motors Ambassador, 1967-1969 American Motors Ambassador
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota 4Runner
Item LocatedUnited States
Quantity1
Part interchange
3004, P16R, 09482-00167, 98079-551-46S, 98079-551-32S, 98079-551-46, 98079-551-32, 90919-01115, 
...View more
item #1002H9XT
Show less
Bosch 79002 Spark Plug
BoschPart # 79002
Bosch 79002 Spark Plug
54 Reviews
$7.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1990-1994 Nissan D21, 1990-1995 Nissan Pathfinder, 1993-1998 Nissan Quest, 1995-1995 Nissan Pickup, 1990-1991 Toyota Celica, 1991-1991 Toyota MR2, 1992-1992 Toyota MR2, 1992-1994 Toyota Paseo, 1995-1995 Toyota Paseo, 2000-2000 Toyota 4Runner, 2001-2004 Toyota Tacoma, 2001-2004 Toyota Tacoma
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota 4Runner
Item LocatedUnited States
Quantity1
Part interchange
79002
item #1002AA1H
Show less
Denso 5304 Spark Plug
DensoPart # 5304
Denso 5304 Spark Plug
44 Reviews
$15.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1992-1992 Acura NSX, 1992-1993 Acura Integra, 1994-1997 Acura Integra, 1994-2005 Acura NSX, 1996-1996 Acura SLX, 1997-1997 Acura Integra, 1998-1998 Acura Integra, 1998-1998 Acura Integra, 1999-2001 Acura Integra, 2000-2001 Acura Integra, 1994-1995 Alfa Romeo 164, 1990-1991 Audi Coupe Quattro, 1992-1993 Audi 100, 1992-1994 Audi 100 Quattro, 1992-1994 Audi S4, 1993-1995 Audi 90, 1993-1995 Audi 90 Quattro, 1994-1994 Audi 100, 1994-1998 Audi Cabriolet, 1995-1997 Audi S6
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota 4Runner
Item LocatedUnited States
Quantity1
Part interchange
5304, 22401 AA530, 22401 AA65A, 32 00 9439, 22401 AA450, 22401 AA550, 22401 AA370, 22401 AA310, 
...View more
item #1004Z286
Show less
Denso 5301 Spark Plug
DensoPart # 5301
Denso 5301 Spark Plug
44 Reviews
$15.99
Edit ZIP code
3-year warranty
90 days free return
Fits 1990-1991 Acura Integra, 1988-1994 BMW 750iL, 1991-1992 BMW 850i, 1993-1994 BMW 850Ci, 1994-1995 BMW 850CSi, 1985-1985 Buick Electra, 1985-1985 Buick LeSabre, 1985-1985 Buick Riviera, 1986-1986 Buick LeSabre, 1986-1987 Buick Regal, 1986-1989 Buick Electra, 1988-1989 Buick LeSabre, 1986-1986 Cadillac Fleetwood, 1987-1989 Cadillac Brougham, 1990-1990 Cadillac Brougham, 1986-1986 Chevrolet Caprice, 1986-1986 Chevrolet Caprice, 1987-1987 Chevrolet Caprice, 1987-1988 Chevrolet Caprice, 1988-1988 Chevrolet Nova
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: Toyota 4Runner
Item LocatedUnited States
Quantity1
Part interchange
5301, IQ16, 22401-01P15, 90919-01152, 90919-01153, 90919-01121-83, 90919-01151, 90919-01151-83, 
...View more
item #1004Z616
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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Spark plugs replacement for cold starts: fix crank no start, cold start misfire, and ignition coil symptoms in winter.

Aug 17, 2026

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Aug 10, 2026

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

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Aug 07, 2026