N5X Spark Plug Gap Tool + Feeler Gauge

Spark Plug Gap Tool & Feeler Gauge — BMW E9X (N5X Engine) Compatible

Dial in your ignition system the way BMW's N-series inline-six deserves. This combination spark plug gap tool and wire feeler gauge is built for E9X 3 Series owners (E90 sedan, E91 wagon, E92 coupe, E93 convertible) running N52, N54, or N55 engines — covering everything from the naturally aspirated 328i/330i to the twin-turbo 335i and single-turbo 335is/335i.

Getting plug gap right matters more on these engines than most. Many aftermarket replacement plugs ship pre-gapped for naturally aspirated applications, and running that gap on a turbocharged N54 or N55 can overload the ignition coils, leading to misfires, rough idle, and premature coil failure — a problem plenty of E9X owners have chased down the hard way. This tool lets you check and correct gap in seconds, before the plug ever goes in the engine, so you're setting up the ignition system for the way your car is actually built rather than trusting a factory setting that may not match your engine.

The stamped-steel body combines a wire-style feeler gauge with a built-in bending slot in one compact piece that fits in a glovebox, tool roll, or spark plug kit. Slide the correct wire between the center and side electrodes for a true reading — wire gauges read the round electrode shape more accurately than a flat blade gauge — then use the bending slot to gently adjust the side electrode until you're on spec. No separate pliers, no guesswork, no bent electrodes from improvising with a screwdriver.

Whether you're doing a routine plug change, swapping in new coils, or chasing a misfire code, this is the tool that takes the gap variable off the table before you ever button up the valve cover.

Ideal for: BMW E90/E91/E92/E93 3 Series equipped with N52, N54, or N55 engines — routine plug service, coil and plug replacement, and misfire diagnostics.

What's included: one combination wire feeler gauge / gapping tool.

Note: Always confirm the correct gap for your specific engine and plug against BMW's spec (or your plug manufacturer's spec for your application) before installation — recommended gap differs between naturally aspirated and turbocharged N5X variants.