Denso
U-Groove Conventional

Denso 4136 Spark Plug

Brand Denso 4136
Resistance 5000
Ground Electrode Tip Design U-groove
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 20.6
Manufacturer Heat Range 24
Seat Type Flat
Reach 19.00
Thread Diameter 14.00
Product line U-Groove Conventional
Fits Maserati · 52 vehicles

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

Copper core. Helps promote consistent spark delivery and dependable operation.

Conventional spark plug. A straightforward ignition component for routine replacement.

Cross-references DENSO Auto Parts W24EPR-U for the same application. See all 1.

$10.05Free 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 $10.05
Free shipping to the continental U.S.
Free returns within 60 days if it doesn't fit when fitment is verified.

Denso 4136 Spark Plug for Maserati

The Denso 4136 is a conventional spark plug built for reliable secondary ignition performance in select Maserati applications. Its U-groove ground electrode design helps improve ignitability for more efficient combustion, while the copper core and nickel electrode materials support consistent spark delivery.

Key Features

  • U-groove ground electrode design for improved ignitability
  • Conventional spark plug construction for select OEM-style applications
  • 5000 ohm resistance for controlled ignition performance
  • Copper center electrode core for stable heat transfer
  • Nickel center and ground electrode tip materials
  • Pre-gapped to 0.8 mm
  • Flat seat design, 14.00 mm thread diameter, 19.00 mm reach
  • 20.6 mm hex size and manufacturer heat range 24

Product Details

Denso U-Groove Conventional spark plugs are engineered around a ground electrode shape that exposes more of the spark kernel, helping the plug fire cleanly under demanding combustion conditions. For Maserati 425, Maserati Spyder, and Maserati Biturbo applications, the Denso 4136 offers a direct-fit ignition service part with the dimensions and electrode materials needed for proper secondary ignition performance. This part cross-references DENSO Auto Parts (e.g., W24EPR-U) for the same application.

What It Helps Address

  • Hard starting caused by worn or fouled spark plugs
  • Rough idle from inconsistent spark delivery
  • Misfire conditions related to degraded ignition performance
  • Reduced combustion efficiency from excessive plug wear
  • Maintenance replacement for aging Maserati ignition service intervals

Installation Notes

Verify thread diameter, reach, seat type, and heat range before installation. The Denso 4136 is specified with a 14.00 mm thread diameter, 19.00 mm reach, flat seat, and 0.8 mm pre-gap. Confirm the vehicle application against the listed fitment for 1984 Maserati Biturbo, 1986-1987 Maserati 425, and 1986-1987 Maserati Spyder. Use proper spark plug service procedures and torque specifications for the engine.

Quality Assurance

Denso’s U-Groove Conventional line focuses on dependable ignition performance through electrode geometry and material selection. The 4136 is built to the listed specifications for consistent fitment and service in the confirmed Maserati applications.

This part fits 52 vehicles
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelNotes
2004KawasakiKX125A & B; U-Groove Conventional
2004PolarisVirageU-Groove Conventional
2003PolarisVirageU-Groove Conventional
2002PolarisFreedomU-Groove Conventional
2002PolarisVirageU-Groove Conventional
2001KTM125 EXCU-Groove Conventional
2001KTM125 SXU-Groove Conventional
2001PolarisPro 1200U-Groove Conventional
2001PolarisSLHU-Groove Conventional
2001PolarisSLXU-Groove Conventional
2001PolarisVirageU-Groove Conventional
2000KTM125 EXCU-Groove Conventional
2000KTM125 SXU-Groove Conventional
2000PolarisPro 1200U-Groove Conventional
2000PolarisSLHU-Groove Conventional
2000PolarisSLXU-Groove Conventional
2000PolarisVirageU-Groove Conventional
1999KTM125 EXCU-Groove Conventional
1999KTM125 SXU-Groove Conventional
1999PolarisSLHU-Groove Conventional
1999PolarisSLTHU-Groove Conventional
1999PolarisSLTXU-Groove Conventional
1999PolarisSLXU-Groove Conventional
1998KTM125 EXCU-Groove Conventional
1998KTM125 SXU-Groove Conventional
1998PolarisSLTXU-Groove Conventional
1997PolarisHurricaneU-Groove Conventional
1997PolarisSL 1050U-Groove Conventional
1997PolarisSL 700U-Groove Conventional
1997PolarisSL 780U-Groove Conventional
1997PolarisSL 900U-Groove Conventional
1997PolarisSLT 780U-Groove Conventional
1997PolarisSLTXU-Groove Conventional
1996PolarisHurricaneU-Groove Conventional
1996PolarisSL 780U-Groove Conventional
1996PolarisSL 900U-Groove Conventional
1996PolarisSLT 780U-Groove Conventional
1996PolarisSLTXU-Groove Conventional
1996PolarisSLX 780U-Groove Conventional
1995SuzukiRM125Spark plug with a hot heat range; U-Groove Conventional
1995SuzukiRM250U-Groove Conventional
1994SuzukiRM125Spark plug with a hot heat range; U-Groove Conventional
1994SuzukiRM250U-Groove Conventional
1993SuzukiRM125Spark plug with a hot heat range; U-Groove Conventional
1993SuzukiRM250U-Groove Conventional
1992SuzukiRM125Spark plug with a hot heat range; U-Groove Conventional
1992SuzukiRM250U-Groove Conventional
1987Maserati425U-Groove Conventional
1987MaseratiSpyderU-Groove Conventional
1986Maserati425U-Groove Conventional
1986MaseratiSpyderU-Groove Conventional
1984MaseratiBiturboU-Groove Conventional
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 — W24EPR-U