Bosch 7401 Spark Plug

Bosch Nickel Spark Plug 7401 Overview

Bosch 7401 is a conventional nickel-copper spark plug built for steady ignition performance and OE-style service life. It uses a heavy-duty yttrium-enhanced nickel center electrode with a copper core, along with a resistor design and preset gap for straightforward replacement in supported vehicles.

For drivers servicing Audi A4, Audi A6, Volvo S60, or Volkswagen Passat applications, Bosch Nickel line spark plugs provide a practical replacement option that follows original equipment specifications for nickel-copper core plugs.

Key Features

• Part number 7401 Bosch spark plug for secondary ignition service
• Nickel-Yttrium center and ground electrode materials with copper-core construction
• Resistor spark plug with 5000 resistance
• Preset 1.35 mm gap; do not gap before installation
• Multiple ground electrode design with 4 ground electrodes
• Flat seat, 14 mm thread diameter, 19 mm reach, and 16 mm hex size
• Ceramic insulator with non-projected insulator type

Detailed Description

Bosch Nickel 7401 is engineered as a conventional 4-cycle spark plug for vehicles that call for a nickel-copper style ignition component. The nickel-yttrium center electrode and copper core are selected to support consistent spark delivery and durable service in everyday driving. The multiple ground electrode configuration and preset gap help maintain the original ignition setup specified for many Audi, Volvo, and Volkswagen engines.

This Bosch 7401 spark plug is listed for 1992-2007 Volvo 960, S70, S80, S90, V70, and V90 applications, plus 1997-2001 Audi A4, A4 Quattro, A6, A6 Quattro, and S4, and 1998-2005 Volkswagen Passat coverage. It also fits select Volvo S60 and S80 models. This part cross-references no additional part numbers in the provided data.

Common Issues This Part Can Address

• Hard starting caused by worn spark plug electrodes
• Rough idle from inconsistent ignition firing
• Misfire conditions related to aged plugs
• Reduced throttle response from degraded spark delivery
• Maintenance replacement for OE-style nickel-copper spark plug service

Installation Notes and Tips

• Install only in listed applications and verify engine-specific fitment before purchase.
• Do not gap this spark plug; the gap is preset from the factory.
• Use the correct torque procedure for the flat-seat design to avoid thread or sealing damage.
• Inspect ignition wires, coils, and boots during replacement to help prevent repeat misfire concerns.
• Confirm the vehicle calls for a 14 mm thread, 19 mm reach, and 16 mm hex spark plug before installation.

Quality Assurance

Bosch designs the Nickel line to meet or exceed original equipment specifications for nickel-copper core spark plugs. The Bosch 7401 follows that OE-style construction approach for supported Audi, Volvo, and Volkswagen applications.