Bosch FR91X Spark Plug
Specs, cross-brand equivalents, vehicle fitment, and live prices for the Bosch FR91X.
The Bosch FR91X is a 14mm thread, 19mm reach, gasket seat, copper electrode spark plug, pre-gapped to 0.043. These specifications are decoded from the Bosch part number and determine which plugs it safely cross-references to — a valid equivalent must match the thread, reach, seat and heat range.
Cross-reference equivalents
| Brand | Part | Metal | Buy |
|---|---|---|---|
| Bosch | FLR8LDU | Copper | Buy |
| Bosch | FLR9LTE | Copper | Buy |
| Bosch | FR91 | Copper | Buy |
| FC42LS2E | — | Buy | |
| RFC42LS2E | — | Buy | |
| RFC42LZ2E | — | Buy | |
| RFC50LZ2E | — | Buy |
Vehicles the FR91X fits
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