Snowfa Garage and Motorsports · Genuine BMW Parts
Genuine BMW "High Power" Spark Plugs — Set of 6
12122455258
The factory iridium plug for the B58 turbocharged straight-six — M240i to X7,
Z4 to GR Supra. Six plugs, one box, the whole engine.
What you're buying
| Part |
Six genuine BMW spark plugs — a complete engine set, new in BMW packaging |
| Part number |
12122455258 (also written 12-12-2-455-258) — supersedes 12120046646 |
| Spec |
BMW's "High Power" iridium plug — the factory spec for the turbocharged straight-six, pre-gapped and ready to fit |
| Fits |
Every B58 3.0L straight-six — 40i-badge BMWs and the Toyota GR Supra 3.0 |
| Origin |
Made in France for BMW |
Know your part numbers
12120046646 → 12122455258
BMW replaced the original number
12120046646 with
12122455258 — same plug, current production number, which
is why the early B58 cars are covered too. Some catalogs also show
12120055028; that's this plug as well.
Driving a GR Supra? Toyota's part number
90118-WA461 is this exact plug — the Supra's 3.0 is a
BMW engine, and this is what your Toyota dealer fits, without the Toyota box markup.
Sold as a complete set of six — one box does the whole straight-six.
Fitment — the B58 straight-six family
| Chassis |
Models |
Years |
| G20 / G22 / G23 / G26 |
M340i · M440i — sedan, coupe, convertible, Gran Coupe, incl. xDrive |
2019–2025 |
| G42 |
M240i · M240i xDrive coupe |
2022–2025 |
| G14 / G15 / G16 |
840i coupe · convertible · Gran Coupe, incl. xDrive |
2020–2025 |
| G01 / G02 / G05 / G06 / G07 |
X3 M40i · X4 M40i · X5 xDrive40i · X6 xDrive40i · X7 xDrive40i |
2018–2025 |
| G29 |
Z4 M40i roadster |
2020–2025 |
| J29 (A90 / A91) |
Toyota GR Supra 3.0 — all trims |
2020–2025 |
162 catalogued applications, including the 540i and 740i sedans — the supersession from
12120046646 folds the early B58 cars in as well. See eBay's compatibility table above
for the full list, or message us with your VIN and we'll confirm it before you order.
Before you buy — check your engine.
-
M Performance yes, full M no. M240i, M340i, M440i and the M40i SUVs are
exactly what this set is for — but the real M cars (M2, M3, M4, X3 M, X4 M) run the
S58 with different plugs. Don't fit these to a full M engine.
-
35i badge? Different era. A 335i, 435i, 535i or X5 35i runs the earlier
N55/N54 six — those take different plugs. This set is for the 40i-era B58.
-
Four-cylinder car? A 230i, 330i, 430i or X3 30i doesn't need six plugs —
message us and we'll set you up with the right count.
-
Not sure what you have? Message us with your VIN before ordering — we answer fast.
Fitting them — one set, one afternoon
- Engine stone cold. Pull the engine cover, unplug each ignition coil connector, and lift the coils out.
- Blow the plug wells out with compressed air before a single plug comes loose — grit dropping into a cylinder is the one mistake you can't undo.
- Old plugs out, new plugs threaded in by hand until seated, then torque to 23 Nm with a torque wrench — never by feel on an aluminum head.
- Coils back in until they click, connectors on, cover on. No coding, no adaptation — just a cleaner idle.
The plugs come pre-gapped — check if you like, but never lever on an iridium tip. BMW's
schedule has plugs due around every 60,000 miles; halve that on a tuned car. While the
coils are out, give them a look — and if you're doing a full B58 service, the genuine
oil filter is 11427826799 — search our store.
Shipping & returns
| Ships from |
Eureka, California — free shipping, carefully packed, fast handling |
| Returns |
30-day free returns — we pay the return shipping |
| Seller |
Top Rated Plus · 9,400+ parts sold · 99.8% positive feedback |
Snowfa Garage and Motorsports — Genuine BMW and performance parts,
new inventory every week. We sell only genuine OEM parts: what's pictured is what ships.
Fitment questions? Message us with your VIN — we answer fast.