BMW 118I Common Problems

The BMW 1 Series is BMW's small hatch, sold here from the 116i to the M140i. The rear-drive E87 hatch (2004 to 2011), E82 coupe and E88 convertible used N45 and N46 four-cylinder petrols, the N52 six in the 130i and 125i, the N54 twin-turbo in the 135i and M47 and N47 diesels. The rear-drive F20 (2011 to 2019) started with the N13 1.6 turbo, N20 and N47, then moved to B38, B48 and B47 engines, with the N55 M135i and B58 M140i on top and a ZF 8-speed auto in most cars. The front-drive F40 (2019 to 2024) pairs the 118i's B38 with a 7-speed dual-clutch, and the F70 arrived late in 2024. Reputation: good gearboxes and chassis, but several engines with well-known timing chain and fuel system faults.

Timing chain failure (N47 diesel 118d, 120d and 123d, 2007 to 2015)

The N47 2.0-litre diesel has its timing chain at the back of the engine, against the gearbox. The chain wears and can snap, and on engines built from March 2007 to early 2009 the crankshaft sprocket teeth can damage it. Failures are still reported on later N47s up to 2015. The warning sign is a rattle or loud ticking from the rear of the engine, often worst from cold. If the chain breaks, valves hit pistons. A chain, guides and tensioner job at a specialist is roughly $2,000 to $4,000 because the engine usually comes out. A broken chain can mean a replacement engine.

Timing chain and fuel pump wear (N13 116i and 118i, N20 125i, 2011 to 2015)

The 1.6-litre N13 turbo in early F20 116i and 118i models belongs to the BMW and Peugeot-Citroen Prince engine family. Timing chain and tensioner failures are documented on this engine family, and owners of F20 116i and 118i models describe a rattle lasting a few seconds after a cold start as the chain stretches. High-pressure fuel pump failures (long cranking, rough running, a warning light) are also reported on the Prince family. The N20 2.0-litre turbo in the 2012 to 2015 125i had plastic chain guides that could break on early engines. Caught early, a chain kit at a specialist is likely to cost roughly $2,000 to $3,000.

Oil leaks and timing chain stretch (N45 and N46 petrol, 2004 to 2011)

The E87 116i, 118i and 120i four-cylinders are simpler engines, but they are now old. Leaking valve cover gaskets, Valvetronic faults (rough idle, warning lights) and timing chain stretch are the complaints parts and repair guides list most for these engines. Resealing a valve cover should be a few hundred dollars. Chain and Valvetronic work costs far more, so listen for a rattle on start-up and check for warning lights.

Fuel pump, wastegate and VANOS faults (N52, N54 and N55 sixes, 2007 to 2013)

The 135i's N54 twin-turbo is known for high-pressure fuel pump failure: long cranking, a warning light and limp-home mode. BMW ran a technical campaign in Australia to replace pumps in an affected VIN range. Slack in the wastegate linkage causes a metallic rattle and, with wear, low boost and limp mode. Leaking piezo injectors and misfires are also reported. On the N52 and N55, loose or broken VANOS bolts caused rattles, power loss and limp mode on cars built around 2009 to 2011, and early N52s (built before late 2008) can tick from the lifters on cold starts. Oil filter housing gasket leaks are widely reported on all three. A fuel pump fitted is likely to cost a couple of thousand dollars, and a set of injectors several thousand.

Cooling system leaks (all engines, 2004 to 2019)

Plastic radiators, hoses, pipe fittings, pulleys and water pumps sit in engine heat and need replacing as the kilometres build. Owners report split radiator pipes and coolant leaks from the thermostat housing at the back of the engine. The six-cylinders and the N20 use an electric water pump that can fail without warning, which brings an overheating warning. A water pump and thermostat on these engines can cost over $1,000.

Low-speed dual-clutch hesitation (118i 7-speed DCT, 2019 to 2024)

The F40 is newer and has no well-documented fault pattern yet. Some buyer guides report hesitation or judder from the 7-speed dual-clutch in stop-start traffic, which a dealer software update may ease. The M135i xDrive and 128ti use an 8-speed torque-converter auto instead. Buy one with a full service history and take a long test drive in traffic.

Recalls and safety

Takata airbags are the main theme. Many E8x cars were covered by Takata driver's airbag recalls, F20 and F21 cars built from late 2013 to 2017 were in a later staged campaign, a 2024 recall checked cars fitted with a different steering wheel after production, and a 2025 recall told owners of some cars with a special edition sports steering wheel not to drive them until the airbag was replaced. Other recalls covered diesel fuel filter heaters that could short and catch fire (2008 to 2009 diesels), the main battery cable at the fuse box (2007 to 2011), a brake vacuum pump (2012 to 2013 F20), VANOS bolts (2009 to 2012) and, in 2026, EGR coolers on a range of BMW models sold from 2010 to 2022, including some 1 Series. Have a BMW dealer check the VIN for open recalls, and see our recalls page.

Buying a used BMW 1 Series? What to check

• Cold start: Start the engine cold yourself. A rattle from the rear on an N47 diesel, or a rattle lasting more than a few seconds on an N13, points to the timing chain.
• Chain and service records: Ask for invoices for any timing chain work and look for oil changes every 10,000 to 15,000 km rather than the longest intervals.
• Oil leaks: Look around the valve cover and oil filter housing, and under the car, and sniff for burning oil after the drive.
• Cooling system: Check the coolant level and look for crusty residue around the radiator, hoses and thermostat housing.
• 135i specifics: Listen for long cranking and wastegate rattle on a light throttle, ask whether the fuel pump campaign was done, and be wary of tuned cars.
• Gearbox: The auto should leave Park cleanly and shift smoothly; on an F40 118i, crawl in traffic to feel for judder.
• Tyres and suspension: Run-flat tyres are dear and wear fast on the edges; listen for knocks over bumps and check the alignment.
• Electrics: Test every window, the iDrive screen, the tail lights and the boot LED strip, and look for water inside the light clusters.

Run a PPSR check for finance and write-off history, then work through our BMW 1 Series buying checklist.

The verdict

The easiest 1 Series to own are the 2015 to 2019 F20 118i, 120i and 125i with B38 and B48 engines and the 8-speed auto, and the F40 118i, M135i and 128ti with full dealer history. Buy a 2011 to 2015 116i or 118i (N13) or any N47 diesel only with proof of timing chain work and a quiet cold start. The E87 118i and 120i are cheap but ageing, so budget for leaks and cooling parts. A 135i is quick and characterful, but needs a specialist inspection and a repair fund.