Professional Iridium Spark Plug
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ACDelco Professional Iridium Spark Plug

Part No. 41-103 Warranty Details  

See if this part fits a specific vehicle.

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ACDelco is a global leader in automotive replacement parts and related services and offers quality aftermarket products for most makes and models, including General Motors, Ford, Chrysler, Toyota and Honda, plus many original equipment service replacement parts. ACDelco products can be found in more than 100 countries located on six of the seven continents and are sourced globally to meet the needs of the local markets, including "maintenance" parts commonly replaced during the lifetime of a vehicle (e.g., batteries, oil filters, air filters, wiper blades, shocks and brakes), as well as "repair" parts (e.g., alternators, radiators, chassis and heating/cooling components). ACDelco offers more than 80,000 parts across 37 product lines.

ACDelco has over 100 years of experience in the automotive industry and is a brand of GM Customer Care and Aftersales, a division of General Motors. ACDelco employs a two- or three-tiered distribution model, utilizing a network of appointed wholesale distributors to service independent installers, ACDelco independent service centers, retail and fleet customers.

Product Features:

  • The kind of firepower you expect from ACDelco. The spark plug is what started it all for us, and with over 100 years of innovation behind each spark plug, you know they're going to be great. From the old to the new and even the non-automotive, ACDelco has a spark plug to fit just about whatever your need may be.
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Electrode Core Material:Copper
Electrode Tip Material:Iridium
Resistor:Yes
Seat Type:Tapered
Thread Diameter:14 mm

REVIEW SNAPSHOT®

by PowerReviews
ACDelcoProfessional Iridium Spark Plug
 
4.7

(based on 49 reviews)

Ratings Distribution

  • 5 Stars

     

    (40)

  • 4 Stars

     

    (5)

  • 3 Stars

     

    (2)

  • 2 Stars

     

    (1)

  • 1 Stars

     

    (1)

96%

of respondents would recommend this to a friend.

Pros

  • Improves engine efficiency (32)
  • Increases power (31)
  • Easy to install (24)
  • Durable (22)
  • Lightweight (8)

Cons

  • Difficult to install (3)

Best Uses

  • Everyday driving (35)
  • Replacement (29)
  • Performance driving (6)
    • Car & Truck:
    • Casual driver (3)
    • Was this a gift?:
    • No (8)
    • Reviewer Profile:
    • Casual driver (24), Auto enthusiast (12), Mechanic (7), Truck enthusiast (4)

Most Liked Positive Review

 

Great plugs!

I bought these plugs for my new to me 2002 Chevy Trailblazer. It ran good, but just didn't feel like it had as much power as it should have. Did my research, and...Read complete review

I bought these plugs for my new to me 2002 Chevy Trailblazer. It ran good, but just didn't feel like it had as much power as it should have. Did my research, and found that this SUV loves the AC Delco 41-103 plugs. Went out and pulled the plugs in it and found $2 AutoLite plugs in it. The next day I got the Delcos, popped them in, and my Trailblazer is running like a top. Be careful with these as they are Iridium plugs and can't be gapped in the traditional manner like your standard plugs can.

VS

Most Liked Negative Review

 

Fine tune up, ready for another 50K

My old AC Delco spark plugs showed some usage at 50,000 miles. Mechanic said they could have gone the full 100,000 miles. However, I felt a tune up at 50,000 with the AC...Read complete review

My old AC Delco spark plugs showed some usage at 50,000 miles. Mechanic said they could have gone the full 100,000 miles. However, I felt a tune up at 50,000 with the AC Delco spark plugs with Iridium would only improve my gas mileage and provide a better performaning vehicle. Tune up at 50,000 may have been overkill, but the ride is a smooth one.

Reviewed by 49 customers

Displaying reviews 1-10

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5.0

I would buy it again!!

By 

from Berwyn, Illinois

Verified Buyer

Comments about ACDelco Professional Iridium Spark Plug:

Great experience

  • Was this a gift?:
  • No
 
5.0

OEM is always best

By 

from Birmingham Alabama

See all my reviews

Verified Buyer
3 or more reviews submitted

Comments about ACDelco Professional Iridium Spark Plug:

My GMC Canyon had Autolites in it when I bought and it had a ran very rough. When I put the plugs back in it that came in it everything smoothed out

  • Was this a gift?:
  • No
 
2.0

Impossible to gap

By 

from Brownsburg indiana

See all my reviews

Verified Buyer
3 or more reviews submitted

Comments about ACDelco Professional Iridium Spark Plug:

The gap for the vehicle i purchased these for was .43 out of the box they were gapped all over the place. The tips are so thin if you try to expand the gap the tip will break off.

  • Was this a gift?:
  • No
 
5.0

A+++

By 

from Laredo, TX

Verified Buyer

Comments about ACDelco Professional Iridium Spark Plug:

My mechanic said best choice on buying Adelco spark plugs

  • Was this a gift?:
  • No
 
5.0

Sparkplugs

By 

from Westminster, MD

Verified Buyer

Comments about ACDelco Professional Iridium Spark Plug:

For my car

  • Was this a gift?:
  • No

(0 of 1 customers found this review helpful)

 
5.0

Pre-gapped convenience

By 

from Long Island, NY

See all my reviews

Verified Buyer

Pros

  • Good For 100k Miles
  • Oem Replacement

Cons

    Best Uses

    • Tune Up

    Comments about ACDelco Professional Iridium Spark Plug:

    Pre-gapped convenience. Make sure to ckeck for rebate - 2 dollars per plug.

    • Was this a gift?:
    • No
     
    5.0

    Great plugs

    By 

    from Hamlin, PA

    Verified Buyer

    Comments about ACDelco Professional Iridium Spark Plug:

    Can't get much better than these

    • Was this a gift?:
    • No
     
    5.0

    I would by this product again and again

    By 

    from Whiting,IN

    Verified Buyer

    Comments about ACDelco Professional Iridium Spark Plug:

    Original equipment plus iridium.... simply the best product for my hummer h3

    • Was this a gift?:
    • No
     
    5.0

    Good plugs!

    By 

    from Broken Arrow, Oklahoma

    About Me Casual Driver

    See all my reviews

    Verified Buyer
    3 or more reviews submitted

    Pros

    • Durable
    • Improves Engine Efficiency
    • Increases Power
    • Lightweight

    Cons

    • Difficult To Install

    Best Uses

    • Everyday Driving
    • Replacement

    Comments about ACDelco Professional Iridium Spark Plug:

    The plugs are difficult to install, but that is the vehicle manufacturers fault. It shouldn't be that difficult to install a set of plugs.

     
    5.0

    Spark Plugs

    By 

    from Tennessee

    About Me Mechanic

    See all my reviews

    Verified Buyer
    3 or more reviews submitted

    Pros

    • Durable
    • Easy To Install
    • Improves Engine Efficiency
    • Increases Power

    Cons

      Best Uses

      • Everyday Driving
      • Replacement

      Comments about ACDelco Professional Iridium Spark Plug:

      Great price and product when I needed it !

      Displaying reviews 1-10

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      Do you have questions about this product?

       

      Ask a question, get answers from real customers and in-house experts. For further assistance, please review your support options on our Contact Us page.

      7 Questions | 9 Answers
      Displaying questions 1-7
      • Q:

        My manual says .042 gap and these are .043 I thought you are not supposed to gap iridium due to the electrode breaking? Can anyone help?
        Asked on 10/19/2016 by Bob from FL

        2 answers

        • CUSTOMER CARE

          A:

          Hi Bob, glad to assist you! This spark plug traditionally leaves the factory pre-gapped for their most popular application. However, the fact remains that the gap must be adjusted for the vehicle that the spark plug is intended for. Those with modified engines must remember that a modified engine with higher compression or forced induction will typically require a smaller gap settings.

          Answered on 10/20/2016 by Steve from AAP
        • CUSTOMER CARE

          A:

          Hi H2, glad to assist you! This spark plug traditionally leaves the factory pre-gapped for their most popular application. However, the fact remains that the gap must be adjusted for the vehicle that the spark plug is intended for. Those with modified engines must remember that a modified engine with higher compression or forced induction will typically require a smaller gap settings.

          Answered on 10/20/2016 by Steve from AAP
      • Q:

        My manual says .042 gap and these are .043 I thought you are not supposed to gap iridium due to the electrode breaking? Can anyone help?
        Asked on 10/19/2016 by Bob from FL

        1 answer

        • CUSTOMER CARE

          A:

          Hi Bob, glad to assist you! This spark plug traditionally leaves the factory pre-gapped for their most popular application. However, the fact remains that the gap must be adjusted for the vehicle that the spark plug is intended for. Those with modified engines must remember that a modified engine with higher compression or forced induction will typically require a smaller gap settings.

          Answered on 10/20/2016 by Steve from AAP
      • Q:

        I am buying the AC Delco 41-103 sparkplugs. What size socket do I need?

        Thanks, Glenn
        Asked on 1/8/2013 by Glenn from Snow Hill , N.C.

        1 answer

        • CUSTOMER CARE

          A:

          A 5/8 inch spark plug socket should work on this ACDelco Spark Plug part# 41-103 as the hex size of this spark plug is 16mm. For any further assistance, you may also visit your nearest Advance Auto store or call us directly at 1-877-ADVANCE (238-2623) and one of our representatives there would be more than happy to assist you.

          Answered on 1/9/2013 by Vincent from AAP
      • Q:

        Does the 5/8 inch spark plug socket fit this particular plug? Thanks!
        Asked on 11/30/2012 by Ken from Miami, FL

        1 answer

        • CUSTOMER CARE

          A:

          Yes, a 5/8 inch spark plug socket should work on this ACDelco Spark Plug part# 41-103 as the hex size of this spark plug is 16mm. For any further assistance, you may also visit your nearest Advance Auto store or call us directly at 1-877-ADVANCE (238-2623) and one of our representatives there would be more than happy to assist you.

          Answered on 11/30/2012 by Rick from AAP
      • Q:

        my book says gap.042 & you guys say .043, cant find any ac/Delco .042. the book & you guys say be exact & i am!
        Asked on 6/10/2011 by craig from rocky riveer

        1 answer

        • CUSTOMER CARE

          A:

          These plugs come with the gap already set as 0.043.

          Answered on 6/21/2011 by Vincent from AAP
      • Q:

        Do these have Iridium?
        Asked on 6/6/2011 by jeff from Chesterfield, Va

        1 answer

        • CUSTOMER CARE

          A:

          The material of the electrode tip is made out of iridium.

          Answered on 6/7/2011 by DIY Daniel from AAP
      • Q:

        Do these spark plugs need to be gapped or do they already come pre gapped?
        Asked on 1/9/2011 by Erol from Cocoa Beach, FL

        2 answers

        • A:

          pre gapped at factory settings.if not your gap setting,you must gap for the setting for your car.

          Answered on 8/4/2012 by johnd93 from hull ga
        • CUSTOMER CARE

          A:

          The majority of the time, spark plugs come pre-gapped.

          Answered on 1/11/2011 by Mike the Auto Parts Master from AAP
      Displaying questions 1-7

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