BOSCH Spark Plug User Manual

BOSCH Spark Plug

Specification

Key Features

• Reliable ignition performance.
• Improved fuel efficiency and engine response.
• Corrosion-resistant nickel-plated housing.
• Optimized electrode design for consistent spark generation.
• Reduced misfires and smoother engine operation.
• Available in Copper, Platinum, and Iridium variants for different service life requirements.
• Note: Exact specifications depend on the specific BOSCH spark plug part number.
• If you provide the BOSCH spark plug model number, I can give the precise specifications.

Basic Structure and Principle

• Structure: Wiring nut, ceramic insulator, metal shell, center electrode, side electrode
• Principle: High voltage electricity breaks through the electrode gap to generate sparks, igniting the mixture and pushing the piston

Core parameters

(must match original factory)

• Thread specifications: diameter (M10/M12/M14), length, pitch, error ≤ 0.3mm
• Calorific value: 5-6 commonly used for naturally aspirated; Turbocharged 7-9(faster heat dissipation)
• Electrode gap: 0.8-1.1mm (factory preset, recheck before installation)

Material and lifespan:

• Nickel copper: 20000 to 30000 kilometers
• Single Platinum: 30000 to 40000 kilometers
• Single Iridium: 40000 to 60000 kilometers
• Double Platinum/Iridium Platinum: 60000 to 100000 kilometers

Installation steps

(cold car operation)

• Preparation: Turn off the engine and cool down for 1-2 hours; Power off (unplug the negative terminal of the battery); Clean the dust around the spark plug
• Disassembly: Pull out the ignition coil plug → Disassemble the coil → Loosen counterclockwise with a socket → Hand rotate to remove the old spark plug
• Check new parts: verify model/calorific value/gap; Do not touch the ceramic body with your hands (to prevent electric leakage)
• Installation: Hand screw in the thread (anti-slip teeth)
• (aluminum alloy 15-25N m); Cast iron 20-30N m)
• Tighten with a torque wrench
• No torque wrench: Hand tighten to the bottom and then turn 1/4-1/2 turn
• Reset: Reinstall the ignition coil → plug in the plug → connect the battery → test drive

Daily inspection and maintenance

• Inspection cycle: Check the gap and carbon deposits every 20000 kilometers; Suggested cleaning/replacement every 40000 kilometers
• Normal state: The insulator is brown/gray-white, and the electrode is not ablated

Abnormal judgment:

• Blackened carbon deposition: excessive mixture, low calorific value, dirty air filter
• Whitening and erosion: premature ignition, high calorific value, detonation
• Oil pollution: burning engine oil, piston ring/valve oil seal issues

Taboos and Precautions

• Hot car replacement (easy to slip/break teeth)
• Mixing different brands/calorific values/thread specifications
• Tighten violently with a regular wrench (vulnerable threads)
• Hand touching ceramic insulation (sweat-induced leakage)
• Foreign objects falling into the cylinder (must be cleaned before installation)

Signs of replacement

(early replacement)

• Idle shaking, weak acceleration, and increased fuel consumption
• Difficulty in cold starting, engine misfire, and exhaust odor
• Electrode erosion, excessive gap, ceramic cracking