Equivalents for the Delphi spark plug D21
The Delphi D21 spark plug — reach 15.2–19.0 mm, heat range hot. Find its 137 compatible and interchangeable spark plugs: cross-references for NGK, Bosch, Champion, Denso and every brand.
Technical information Delphi D21 spark plug
- Resistor
- no
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What can replace a Delphi D21 spark plug?
The Delphi D21 is interchangeable with: Bosch CH177, Champion W640, Denso G106, Champion CH177, Champion GX116, Champion SX116. These spark plugs share the same mounting (thread, seat) and heat range.
What are the specifications of the Delphi D21?
Reach 15.2–19.0 mm, Heat range Hot, Resistor no, Seat Flat (gasket)
Cross-references and specifications are provided for guidance only. The wrench size can vary by brand, and some data is inferred from the plug code or an equivalent reference. Always check the vehicle manufacturer's recommendation before buying and fitting.