Why does my BMW 135i crank a long time and go into reduced power?

Short answer: On the 135i's N54 twin-turbo engine, a long crank before it starts plus an "engine malfunction, reduced power" warning is a classic sign of a failing high pressure fuel pump (HPFP). The HPFP boosts fuel pressure for the direct injectors. Owners say dealers replaced many under a BMW bulletin, and they recommend genuine pumps over cheap ones. Leaking injectors can cause similar symptoms.

Symptom: The engine cranks noticeably longer than normal before it starts, then a check engine light or "reduced power" message shows up, sometimes with hesitation or stalling.

What to check first

1. Read the BMW-specific fault codes with a BMW-capable scanner. Owners saw codes like 2FBF and 29F1–29F3.
2. Ask a BMW shop to check low and high fuel pressure.
3. Check the injectors too. One owner needed an injector as well as a pump.
4. Ask a BMW dealer about past or current coverage for your VIN.
5. Check your VIN for open recalls, such as 14V176 (VANOS bolts on some 2011–2012 135i).

Likely causes

1. Failing high pressure fuel pump (HPFP). The most common cause owners report.
2. Leaking or failing fuel injector. Can cause misfires and similar warnings.
3. Low-pressure (in-tank) fuel pump problem. A shop should check both pressures.

What it usually costs

Owners in these threads didn't post total prices. One owner warned against a $200 aftermarket pump and fixed the problem with a genuine BMW pump.

Is it safe to keep driving?

Not for long. Reduced power can show up when you need to accelerate, and the car can stall. Get it checked soon and avoid highway merges until then. Verify with a mechanic.

DIY or shop?

DIY possible for experienced owners. The HPFP is on top of the engine, but you must release fuel pressure safely. Injectors are more involved. Many owners use a BMW specialist.

Recalls, bulletins and complaints in plain words

• No HPFP recall in NHTSA's list for this model: BMW handled pump replacements through a service bulletin (one owner's dealer cited SIB 13 07 09). NHTSA recalls for these cars include VANOS housing bolts that can loosen on some 2011–2012 135i (14V176) and air bag inflator recalls (16V071, 20V017). If your car is part of a recall, the dealer fixes it for free.
• NHTSA complaints: 100 keyword-matched complaints for BMW 1 Series (128i/135i) 2008–2013 (of 435 unique complaints queried, NHTSA complaints API by model year, queried 2026-10-22; keywords: fuel pump, HPFP, long crank, limp mode, reduced power, stall, hesitate). This counts complaints that mention these words. It is not a defect finding.

What owners report

• In My first HPFP replacement.... on 1addicts, a 2009 135i at 7,800 miles had a long crank, then a check engine light with fault 2FBF. The dealer replaced the HPFP under the BMW bulletin.
• In N54 Fuel-related fault codes and symptoms on 1addicts, a 2008 135i at about 217,000 km (about 135,000 miles) had a long crank and "engine fault, restricted power" with codes 29F1, 29F2 and 29F3. After replacing one injector, a genuine BMW HPFP fixed it. The owner warned against cheap aftermarket pumps.

Quick tip

On an N54 car, ask whether the HPFP and injectors have been replaced, and with what brand.

Vehicle focus: 2008–2013 BMW 135i (N54 twin-turbo). Some details may also apply to other N54 BMWs.

Safety / mechanic note

Fuel systems hold high pressure. Release pressure before working on them. Verify with a mechanic.