18i / 20i / 28i (N46 / N20 petrol)
2009–2015 · petrol · 1997cc · 184hp
Engine codes: N46, N20
Reliability, common problems and owner reviews for the Bmw X1 18i / 20i / 28i (N46 / N20 petrol). Check this before you buy used.
The X1 petrols span the older naturally-aspirated N46 (smooth but underpowered and with known timing-chain/VANOS/valve-cover items) and the later turbo N20 (much punchier). The N20 is the one to scrutinise: early units (roughly 2011–2015) are known for timing-chain and tensioner/guide wear that can rattle and, if ignored, fail — BMW revised the parts later. Plus oil-filter-housing gasket and turbo/PCV care. A documented car with the revised/replaced chain and clean oil is good; a rattling early N20 is a warning.
Same engine, other cars
This is the same physical engine (B48) sold under different names across brands. Reliability is broadly shared — cross-check these:
- BMW 1 Series E87— 116i / 118i / 120i (N46, 2004–2007)150hp
- BMW X3 G01— xDrive20i / 30i (B48 2.0 turbo)252hp
- BMW 3 Series G20— 318i / 320i / 330i (B48 2.0 turbo)258hp
- BMW 3 Series F30— 320i / 328i (N20 turbo)245hp
- BMW X3— xDrive20i / 28i (N20 turbo)245hp
- BMW 5 Series G30— 520i / 530i (B48 2.0 turbo)252hp
- BMW X2— sDrive18i / 20i / xDrive20i (B38 / B48)192hp
- BMW 2 Series— 218i / 220i / 230i (B38 / B48 turbo)184hp
- BMW 4 Series— 420i / 430i (B48 / N20 2.0 turbo)252hp
- BMW 3 Series E90— 318i / 320i 2.0 (N46)150hp
Known Issues
Early N20 chain, tensioner and guides wear → rattle; failure damages the engine. Revised later.
Fix / Workaround: Cold-start rattle check; confirm revised parts/replacement; strict oil.
Repair cost: €800–€2500
Typically appears after: 100,000 km
N46 timing chain, VANOS and valve-cover gasket items with age.
Fix / Workaround: Chain/VANOS inspection; replace VCG.
Repair cost: €200–€1200
Typically appears after: 130,000 km
Year Cutoffs
Mileage Thresholds
After 120,000 km: Chain-wear window (N20 esp.).
Pre-Purchase Checklist
- ☐Cold-start chain rattle (N20)
- ☐Revised chain / replacement history
- ☐Oil + OFHG history
Frequently asked questions
Is the Bmw X1 18i / 20i / 28i (N46 / N20 petrol) reliable?
Maint. Sensitive — The X1 petrols span the older naturally-aspirated N46 (smooth but underpowered and with known timing-chain/VANOS/valve-cover items) and the later turbo N20 (much punchier). The N20 is the one to scrutinise: early units (roughly 2011–2015) are known for timing-chain and tensioner/guide wear that can rattle and, if ignored, fail — BMW revised the parts later. Plus oil-filter-housing gasket and turbo/PCV care. A documented car with the revised/replaced chain and clean oil is good; a rattling early N20 is a warning.
What are the common problems and reviews for the Bmw X1 18i / 20i / 28i (N46 / N20 petrol)?
The most commonly reported problems: Timing chain / guides (early N20), N46 chain / VANOS / VCG (older).
Is a used Bmw X1 18i / 20i / 28i (N46 / N20 petrol) worth buying?
Fine if serviced correctly — but it punishes neglect hard. History and the right consumables matter.