Denso 4131 Spark Plug

Brand Denso 4131
Resistance 5000
Ground Electrode Tip Design Standard
Ground Configuration Standard
Ground Electrode Core Material Nickel
Center Electrode Core Material Copper
Center Electrode Tip Material Nickel
Pre-Gap Size 0.8
Ground Electrode Quantity 1
Hex Size 16.0
Manufacturer Heat Range 27
Seat Type Flat
Reach 19.00
Thread Diameter 14.00
Fits —

U-Groove design. Improves ignitability for more efficient engine performance.

Copper core. Helps promote consistent spark delivery.

Nickel electrodes. Built with nickel tip and ground materials for dependable operation.

Cross-references DENSO Auto Parts U27ESR-N for the same application. See all 1.

$13.85Free shipping
In stock · usually ships same day before 1pm CST
Step 1 — Confirm fitment
Free return shipping if it doesn't fit when you check fitment here first.
Select your vehicle to confirm fitment
Verify this part fits before purchasing — free returns if it doesn't
Step 2 — Quantity
Order total $13.85
Free shipping to the continental U.S.
Free returns within 60 days if it doesn't fit when fitment is verified.

Denso 4131 U-Groove Spark Plug Overview

The Denso 4131 spark plug is a conventional U-Groove design built for reliable ignition performance and improved engine efficiency. It uses a copper center electrode core with nickel tip materials and a nickel ground electrode to support consistent spark delivery in everyday driving.

For drivers searching for a Denso spark plug for Honda Civic, Toyota Corolla, or similar secondary ignition applications, this part number 4131 offers a straightforward OE-style replacement with a 0.8 mm pre-gap and a 5000 ohm resistor.

Key Features

  • U-Groove electrode design for improved ignitability
  • Copper center electrode core for stable heat transfer
  • Nickel center and ground electrode tip materials
  • 5000 ohm resistance for controlled electrical performance
  • Standard ground configuration and standard ground electrode tip design
  • Flat seat, 14.00 mm thread diameter, and 19.00 mm reach
  • Manufacturer heat range 27
  • 16.0 mm hex size for proper service tool fitment

Product Details

Denso’s U-Groove Conventional line focuses on dependable spark formation through a shaped ground electrode that helps expose the flame kernel more effectively. On this Denso 4131 plug, the copper core supports thermal conductivity while the nickel electrode materials provide a conventional serviceable construction for routine ignition maintenance. The flat seat and 19.00 mm reach make this spark plug suitable for applications specified to those dimensions, including select Honda Civic and Toyota Corolla engine configurations where the OEM specification calls for this style of plug.

This part cross-references DENSO Auto Parts U27ESR-N for the same application.

Common Issues This Spark Plug Can Address

  • Hard starting caused by worn or fouled spark plugs
  • Rough idle from weak or inconsistent spark output
  • Misfire conditions related to degraded secondary ignition components
  • Reduced fuel efficiency from inefficient combustion
  • Loss of throttle response from aged ignition service parts

Installation Notes and Tips

Verify thread diameter, reach, seat type, and heat range against the vehicle service specification before installation. Confirm the pre-gap setting matches the engine requirement, and inspect ignition wires or coil-on-plug components at the same time to avoid repeat misfire concerns. For fitment-based searches, this spark plug is the type of part used when replacing a Denso 4131 spark plug in Honda Civic or Toyota Corolla secondary ignition service.

Quality Assurance

Denso is an established OE supplier in ignition and engine management components, and the U-Groove Conventional line is built around consistent spark performance and serviceable construction. Part number 4131 is manufactured to the listed specifications for applications that call for this exact plug design.

This part fits 0 vehicles
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelPositionNotes
Directly replaces or cross-references 1 part number
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.
DENSO Auto Parts — U27ESR-N