BMW N54B30 engine code explained
N54B30 is the full code for BMW's first turbocharged straight-six petrol of the modern era, the twin-turbo, direct-injection engine in the 135i, 335i, 535i, X6 35i, Z4 35i and the 1M Coupe from 2006 to 2016. It is a tuner favourite with a matching reputation for high-pressure fuel pump and injector problems, both covered by extended warranties when new. Two tiers covered every application.
Quick answer
The N54B30 is the 3.0-litre straight-six twin-turbo petrol of the BMW N54 family, built 2006-2016. Bimmer.AI scores the family 6 / 10: a sound used buy provided the known weak points are documented. The tables below give every output tier and sticker letter BMW used on this stem and which cars got them; the failure table is the same one that powers the N54 family guide.
How to read N54B30
| Part of the code | Meaning |
|---|---|
| N | N-series engine generation (2001 to about 2015) |
| 54 | engine family number within the N-series |
| B | petrol, longitudinal (rear-drive platform: 1 to 8 Series, X3 to X7, Z4) |
| 30 | displacement in tenths of a litre: 3.0 litres |
| K / U / M / O / T / S + digit | output tier and revision, appended in BMW's internal naming (for example N54B30O1) |
| A / B / C / D | parts-catalogue engine version printed on the engine cover sticker (for example N54B30A) |
N54B30 output tiers and which cars have them
| Code | Output | Cars | Notes |
|---|---|---|---|
| N54B30M0 | 306 bhp | 135i (E82 / E88 2008-2010), 335i (E90 / E91 / E92 / E93 2006-2010), 535i (E60 / E61 2008-2010), X6 xDrive35i (E71 2008-2010), Z4 sDrive35i (E89 2009-2016), 740i (F01, US) | The volume tier |
| N54B30T0 | 320 to 340 bhp | 335is (E92 / E93 2011-2013), Z4 sDrive35is (E89 2010-2016), 1M Coupe (E82 2011-2012) | Top tier with overboost; collectible in 1M form |
N54B30 sticker letters: N54B30A
On the N54 the letter does not help a buyer. What matters is the high-pressure fuel pump (HPFP) and injector history: BMW extended the HPFP warranty to 10 years / 120,000 miles in the US after NHTSA campaign 12V-035 and replaced injectors under separate campaigns. Ask for the receipts, then check the wastegate rattle, charge pipe and oil-filter-housing gasket.
| Sticker code | What it denotes |
|---|---|
| N54B30A | Standard parts-catalogue version for all applications; later production carries the updated HPFP and injector specifications. |
Known problems on every N54B30
Failure data is held once, per engine family, so this table is identical to the BMW N54 guide. Cost ranges are indicative UK figures.
| Failure mode | Severity | Frequency | Typical onset | UK repair range |
|---|---|---|---|---|
| High-pressure fuel pump (HPFP) failure | Serious | Very common | 30 to 130k mi | Free (recall) or up to £900 |
| Fuel injector failure | Moderate | Common | 40 to 130k mi | £350 to £1,500 |
| Plastic charge pipe failure | Moderate | Common | 50 to 130k mi | £120 to £350 |
| Wastegate actuator rattle (twin-turbo, more complex) | Mild | Common | 40 to 100k mi | £400 to £1,200 |
| Intake valve carbon buildup | Moderate | Very common | 60 to 120k mi | £350 to £600 |
| Electric water pump failure | Moderate | Very common | 60 to 110k mi | £450 to £700 |
Long-term verdict
BMW's legendary first modern turbo six. Tuning favourite (stage 1 maps add 80-120 bhp), parts supply is excellent. Two defining buyer concerns: the high-pressure fuel pump (BMW issued an extended warranty / recall) and original injector failure (also covered under extended warranty). With both verified completed and the typical N5x service items addressed, the N54 is a reliable used petrol. Without verification, factor £600-£2,000 of risk.
Check a specific N54B30 listing
Paste any BMW N54 listing, VIN or registration. Bimmer.AI identifies the exact engine and returns the buyer report in 30 seconds.
Run a Bimmer.AI buyer report →Bimmer.AI is designed to help you identify BMW-specific buyer risks before you travel, negotiate, or pay for an inspection. It does not replace a physical inspection by a qualified mechanic, a legal vehicle-history check (e.g. HPI Check), or independent verification of finance, stolen, or write-off status. Repair-cost ranges are indicative UK figures that vary by region, specialist, parts supply, and labour rates.
Frequently asked questions
N54B30 problems: what fails?
In order of buyer importance: the high-pressure fuel pump (long crank, stumble, limp mode; £700 to £1,300), the injectors (rough idle, misfires; £200 to £300 each at an independent, ideally replaced in matched batches), turbo wastegate rattle (a slow death, £1,800 to £3,500 for a turbo pair), the plastic charge pipe (bursts under boost, £150 to £300 for an aluminium one), the oil-filter-housing gasket, and the electric water pump. See the full failure table below.
Is the N54B30 a good engine to buy in 2026?
For an enthusiast with a specialist nearby, yes; for a daily driver on a budget, the later N55B30 is the calmer choice. The N54's iron block and forged internals make it a 500 bhp engine on stock hardware, which is why so many have been tuned. Buy on HPFP and injector receipts, a clean wastegate, and evidence the previous owner was not running Stage 2 on original turbos.
Which BMWs have the N54B30 engine?
The N54B30 went into the following cars, by output tier. N54B30M0 (306 bhp): 135i (E82 / E88 2008-2010), 335i (E90 / E91 / E92 / E93 2006-2010), 535i (E60 / E61 2008-2010), X6 xDrive35i (E71 2008-2010), Z4 sDrive35i (E89 2009-2016), 740i (F01, US); N54B30T0 (320 to 340 bhp): 335is (E92 / E93 2011-2013), Z4 sDrive35is (E89 2010-2016), 1M Coupe (E82 2011-2012). The two-letter family badge is N54; any listing that quotes the family code is talking about one of these.
Is the BMW N54B30 reliable?
Bimmer.AI scores the N54 family 6 out of 10, which makes the N54B30 a sound used buy provided the known weak points are documented. BMW's legendary first modern turbo six. Tuning favourite (stage 1 maps add 80-120 bhp), parts supply is excellent. Two defining buyer concerns: the high-pressure fuel pump (BMW issued an extended warranty / recall) and original injector failure (also covered under extended warranty). With both verified completed and the typical N5x service items addressed, the N54 is a reliable used petrol. Without verification, factor £600-£2,000 of risk.
What does N54B30 mean?
N is the N-series engine generation (2001 to about 2015), 54 is the family number, B means petrol, longitudinal (rear-drive platform: 1 to 8 Series, X3 to X7, Z4), and 30 is the displacement in tenths of a litre (3.0 litres). BMW appends an output tier and revision (K, U, M, O, T or S plus a digit) in its own naming, and the parts catalogue adds a version letter (A, B, C) that is what you see on the engine cover.