Bosch 9691 Spark Plug

Overview of Bosch OE Fine Wire Double Iridium Spark Plug 9691

The Bosch OE Fine Wire Double Iridium Spark Plug 9691 is engineered for reliable ignition performance in select Hyundai, Kia, Mitsubishi, and Smart vehicles. Designed with advanced materials and precise specifications, this spark plug supports efficient combustion and consistent engine operation.

• Part Number: 9691
• Brand Line: OE Fine Wire Double Iridium
• Center Electrode Tip Material: Iridium
• Ground Electrode Tip Material: Platinum-iridium and nickel-yttrium
• Resistance: 6000 ohms
• Pre-Gap Size: 0.7 mm
• Thread Diameter: 12 mm
• Reach: 26.5 mm
• Hex Size: 16 mm
• Manufacturer Heat Range: 7
• Seat Type: Flat
• Insulator Material: Ceramic
• Ground Electrode Quantity: 1
• Spark Plug Type: 4-cycle engines

OE Fine Wire Double Iridium Product Line Details

The OE Fine Wire Double Iridium line from Bosch features spark plugs with fine wire iridium center electrodes combined with platinum-iridium ground electrode tips. This combination enhances durability and ignition efficiency, providing stable spark performance and extended service life. The use of nickel-yttrium and copper in the center electrode core further supports thermal conductivity and electrode strength, making it suitable for modern 4-cycle engines.

Technical Description and Features

This Bosch spark plug 9691 incorporates a 6000 ohm resistor to reduce electrical noise and protect sensitive vehicle electronics. The flat seat design ensures proper sealing and fitment in compatible engines. With a 0.7 mm pre-gap, it is optimized for efficient spark generation. The ceramic insulator is non-projected, providing reliable insulation and heat resistance. The single ground electrode with a standard tip design balances durability and ignition consistency. The 16 mm hex size and 26.5 mm reach match OEM specifications for select Hyundai Elantra, Kia Niro, Mitsubishi Outlander, and Smart Fortwo and Ioniq models.

Compatible Vehicles and Applications

• Hyundai Elantra
• Kia Niro
• Mitsubishi Outlander
• Smart Fortwo
• Smart Ioniq

This spark plug is designed specifically for 4-cycle engines in these models, ensuring proper fit and function.

Common Issues Addressed by Bosch Spark Plug 9691

• Engine misfires due to worn or faulty spark plugs
• Reduced fuel efficiency from incomplete combustion
• Difficulty starting the engine in cold conditions
• Rough idling or hesitation during acceleration
• Ignition system electrical interference

Installation Notes and Tips

Before installation, verify the spark plug gap is set to 0.7 mm as specified. Use a torque wrench to tighten the spark plug to the manufacturer’s recommended torque to avoid damage to the threads or seat. Ensure the spark plug threads are clean and free of debris. It is recommended to replace all spark plugs in the engine simultaneously for balanced performance. This spark plug is intended for use in 4-cycle engines only.

Quality Assurance and Warranty

Bosch OE Fine Wire Double Iridium spark plugs are manufactured to meet strict OEM standards for quality and durability. The use of premium materials such as iridium and platinum-iridium electrodes ensures long service life and consistent ignition performance. While specific warranty details may vary, Bosch products typically come with a limited warranty against manufacturing defects. Consult vehicle or Bosch documentation for exact warranty terms.