The Honda R18A and R20A engines are part of Honda’s R-series inline-4 SOHC i-VTEC engine family, commonly found in models like the Honda Civic, CR-V, and Accord. Both engines use individual ignition coil-on-plug (COP) systems, which means each spark plug has its own dedicated ignition coil mounted directly on top.

Here’s a breakdown of the plug coil description for the R18A and R20A engines:

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Ignition Coil (Plug Coil) Overview

• Type: Coil-On-Plug (COP)
• Function: Converts low-voltage battery power into high-voltage needed to create a spark at the spark plug.
• Number of Coils: 4 (one per cylinder)
• Mounting Position: Directly on top of each spark plug in the cylinder head
• Connection: 3-pin or 4-pin electrical connector (varies slightly depending on generation or model year)

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Typical Specifications