15% OFF ORDERS $35+ | 20% OFF $100+ | ONLINE ONLY
USE CODE
HOLIDAYSAVE
*
Exclusions apply.
Advance Auto Parts Logo
Choose a Store
  • Shop All
  • Replacement Parts
  • Performance Parts
  • Accessories
  • Oil & Fluids
  • Special Offers
  • Speed Perks
  • Advice & How-Tos
  • Project Guides
  • FAQ / Help Desk
Loading...
Share
Product thumb
Product thumb
Product main large
Loading...
How Would You Like To Get This Item?

Store Pickup

Loading...Loading...Loading...

Same Day Home Delivery

Loading...Loading...Loading...

Home Delivery

Loading...Loading...Loading...
Loading...
Loading...
Loading...Loading...Loading...Loading...Loading...

Product Information

Product Details
Part No. AP646
Warranty Details (4 YR REPLACEMENT IF DEFECTIVE)
Autolite Platinum spark plugs are expertly crafted to deliver exceptional performance and durability for older engine applications. Featuring a platinum center electrode firing tip, these spark plugs resist gap erosion, ensuring a longer service life and consistent reliability. The high alumina ceramic insulator enhances thermal conductivity and insulation, providing superior strength under demanding conditions. A multi-rib insulator design prevents flash-over, while the nickel-plated shell offers outstanding corrosion resistance for extended durability. With a necked-down center electrode, these spark plugs fire quicker and cleaner, requiring less voltage for smoother starts, faster acceleration, and improved fuel efficiency. Designed with a mid-projection standard center electrode and a flat seat type, they are tailored for performance-grade applications. The combination of platinum and nickel materials ensures optimal conductivity and durability, making these spark plugs a smart choice for drivers seeking enhanced engine efficiency and long-lasting reliability.

Product Features:
  • Engineered with a platinum firing tip that prevents gap erosion for longer service life.
  • Its high alumina ceramic insulator provides thermal conductivity and superior insulation for increased strength.
  • The multi-rib insulator prevents flash-over.
  • Designed with a nickel-plated shell that is corrosion resistant to provide increased durability for extended life.
  • Necked-down center electrode fires quicker and cleaner with less voltage for easier starts, quicker acceleration, and improved fuel economy
Specifications
Center Electrode Core Material:
Copper

Center Electrode Design:
Standard

Center Electrode Projection:
Mid Projection

Center Electrode Tip Material:
Platinum

Electrical Terminal Type:
Non-Removable Nut

Electrode Tip Material:
Platinum

Grade Type:
Performance

Ground Electrode Core Material:
Nickel

Ground Electrode Quantity:
1

Ground Electrode Tip Design:
Standard

Ground Electrode Tip Material:
Nickel

Hex Size:
13/16 in

Hex Type:
Hex

Indexed:
No

Insulator Material:
Ceramic

Manufacturer Heat Range:
8

Pre-Gap Size:
0.05 in

Reach:
0.75 in

Resistance:
4000 ohm

Resistor:
Suppressor

Resistor Type:
Yes

Seat Type:
Flat

Skirt:
No

Thread Diameter:
14 mm

Tip Configuration:
Power

Washer(s) Included:
Yes

Wrench Diameter:
13/16 in
Loading...
Loading...Loading...Loading...Loading...Loading...
Loading...
Loading...
Loading...Loading...Loading...Loading...Loading...
No results
Loading...
Loading...Loading...Loading...Loading...Loading...
Feedback
Be The First To Know About Deals And Promotions.
Plus, create an account to receive $5 off of $20 or more.
TOP REPLACEMENT PARTS
Brake Pads & Shoes
Brake Rotors
Alternators
Water Pumps
Starters
Brake Calipers

Order Lookup

Help Desk

Store Locator

In Store Services

Mobile App

CUSTOMER SUPPORT
Accessibility Statement
Contact Us
Forgot Password
Help Desk
In Store Pickup
In Store Services
Order Tracking
Recall Information
Return Policy
Same Day Delivery
© 2025 Advance Auto Parts
Privacy Policy
Terms of Use
Site Map
ADVANCING A WORLD IN MOTION®