Professional Iridium Spark Plug
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ACDelco Professional Iridium Spark Plug

Part No. 41-103 Warranty Details  

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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
Spark Plug Seat Type:Tapered
Spark Plug Thread Size:14

REVIEW SNAPSHOT®

by PowerReviews
ACDelcoProfessional Iridium Spark Plug
 
4.6

(based on 37 reviews)

Ratings Distribution

  • 5 Stars

     

    (29)

  • 4 Stars

     

    (5)

  • 3 Stars

     

    (2)

  • 2 Stars

     

    (0)

  • 1 Stars

     

    (1)

97%

of respondents would recommend this to a friend.

Pros

  • Improves engine efficiency (29)
  • Increases power (28)
  • Easy to install (23)
  • Durable (20)
  • Lightweight (7)

Cons

No Cons

Best Uses

  • Everyday driving (31)
  • Replacement (26)
  • Performance driving (6)
    • Car & Truck:
    • Casual driver (3)
    • Reviewer Profile:
    • Casual driver (22), Auto enthusiast (12), Mechanic (5), 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 37 customers

Displaying reviews 1-10

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5.0

OEM replacement is Perfect.

By 

from Mid Michigan

About Me Auto Enthusiast, Mechanic

Verified Buyer

Pros

  • Durable
  • Improves Engine Efficiency
  • Increases Power
  • Lightweight

Cons

    Best Uses

    • Everyday Driving
    • Performance Driving
    • Replacement

    Comments about ACDelco Professional Iridium Spark Plug:

    These plugs last about 100,000 miles in my Trailblazer 4.2. Takes a bit of time to install. The oem plugs are no longer made and these are the new GM recommended replacement. They are top of the line GM plugs.

    Comment on this reviewHelp Icon(earn points)

     
    5.0

    I would use the product again

    By 

    from Ohio

    About Me Casual Driver

    Verified Buyer

    Pros

    • Increases Power

    Cons

      Best Uses

      • Everyday Driving

      Comments about ACDelco Professional Iridium Spark Plug:

      Install them on a 2004 Trailblazer increase the performance

      Comment on this reviewHelp Icon(earn points)

       
      4.0

      Smooth fire

      By 

      from Lexington, KY

      About Me Auto Enthusiast

      Verified Buyer

      Pros

      • Easy To Install
      • Improves Engine Efficiency

      Cons

        Best Uses

        • Everyday Driving
        • Replacement

        Comments about ACDelco Professional Iridium Spark Plug:

        Good spark plug with smooth idle and good power.

        Comment on this reviewHelp Icon(earn points)

         
        4.0

        Nice effecient plug

        By 

        from Sioux city iowa

        Verified Buyer

        Comments about ACDelco Professional Iridium Spark Plug:

        Pre gapped and ready to put in.

        Comment on this reviewHelp Icon(earn points)

         
        5.0

        OEM Exact replacement for a 2007 Chevy Trailblazer 4.2L

        By 

        from WARNER ROBINS, Georgia

        Verified Buyer

        Comments about ACDelco Professional Iridium Spark Plug:

        Don't forget the anti-seize and silicone compound ( dielectric grease )

        Comment on this reviewHelp Icon(earn points)

        (0 of 2 customers found this review helpful)

         
        5.0

        acdelco for chevy

        By 

        from n.j.

        About Me Casual Driver

        Ask me a question

        Verified Buyer
        3 or more reviews submitted

        Pros

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

        Cons

          Best Uses

          • Everyday Driving

          Comments about ACDelco Professional Iridium Spark Plug:

          have 5 cars in driveway,all use ACDelco

          Comment on this reviewHelp Icon(earn points)

          (3 of 3 customers found this review helpful)

           
          5.0

          Great plugs!

          By 

          from Dandridge TN

          About Me Auto Enthusiast, Casual Driver

          Helpful Reviewer

          Pros

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

          Cons

            Best Uses

            • Everyday Driving
            • Replacement

            Comments about ACDelco Professional Iridium Spark Plug:

            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.

            Comment on this reviewHelp Icon(earn points)

            (1 of 4 customers found this review helpful)

             
            5.0

            works better then stock

            By 

            from Philadelphia, PA

            About Me Auto Enthusiast

            Ask me a question

            Verified Buyer
            Level 3

            Pros

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

            Cons

              Best Uses

              • Everyday Driving
              • Performance Driving
              • Replacement

              Comments about ACDelco Professional Iridium Spark Plug:

              This was very east to do and while your there you should replace the spark plugs I used the stock Professional Iridium Spark Plug by ACDelco and since the best way to replace these is to take the 4 bolts out of the throttle body off you should take the time to clean that too.

              Comment on this reviewHelp Icon(earn points)

              (2 of 4 customers found this review helpful)

               
              5.0

              Good OE plugs

              By 

              from CT

              About Me Mechanic

              Verified Buyer
              Level 1

              Pros

              • Improves Engine Efficiency
              • Increases Power

              Cons

              • Decreases Gas Mileage

              Best Uses

              • Replacement

              Comments about ACDelco Professional Iridium Spark Plug:

              Great. Product. No need to go with over the top expensive plugs.

              Comment on this reviewHelp Icon(earn points)

               
              5.0

              I would buy this product again

              By 

              from Upper Sandusky, OH

              About Me Casual Driver

              Verified Buyer
              Level 2

              Pros

                Cons

                  Best Uses

                  • Replacement

                  Comments about ACDelco Professional Iridium Spark Plug:

                  .

                  Comment on this reviewHelp Icon(earn points)

                  Displaying reviews 1-10

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                  Do you have questions about this product?(earn points for answers!)

                   

                  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.

                  5 Questions | 6 Answers
                  Displaying questions 1-5
                  • 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 1-5

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