B48
BMW · 2.0L Turbo I4
2014–present
"B58s little brother. Efficient, smooth. Remap to 260hp safe. Best modern 4-cyl BMW."
Mileage Risk Timeline
When problems typically appear — enter your mileage to see your risk zone
Known Issues 3
Coolant vent line failure
▸Coolant warning light, minor coolant loss
Small coolant vent line can crack or detach. Cheap part, can cause coolant loss if undetected.
Quick visual at any service. €100-250. Low overall risk.
Oil filter housing gasket — early units (2014-2016)
▸Oil drips under car, burning smell, oil residue on underside
Early B48 higher OFHG failure rate. BMW revised gasket material. 2017+ mostly unaffected.
Check service history on pre-2017 cars. If not done and 80k+ km: inspect. €250-500.
Intake valve carbon buildup (DI)
▸Rough idle, slight power loss, cold start misfires
Direct injection = no fuel washing intake valves. Walnut blasting cleans it.
Less concern in Greece — warm climate and highway driving reduce buildup. Clean at 80-100k km if symptoms.
This report covers the combustion engine only. Battery and electric motor reliability are not included.
Models with B48 40
Related Guides
Other BMW Engines
Tuning Potential
260hp Stage 1 safe
Frequently Asked Questions
Is the BMW B48 reliable?
The BMW B48 scores 82/100 with a verdict of BUY. It has 3 documented issues with total repair costs between €650 and €1,350.
What are the common problems with the B48?
The most common issues are:
- Coolant vent line failure — moderate, repair cost €100–€250, 40,000 km–100,000 km
- Oil filter housing gasket — early units (2014-2016) — moderate, repair cost €250–€500, 40,000 km–100,000 km
- Intake valve carbon buildup (DI) — minor, repair cost €300–€600, 60,000 km–120,000 km
What cars use the BMW B48?
How much does it cost to repair the B48?
Total potential repair costs for all 3 known issues range from €650 to €1,350. The most expensive issue is typically .
What years was the B48 produced?
The BMW B48 was produced from 2014 to present. It is a 1998cc I4 petrol turbo engine.
Scores are calculated from documented issues, repair costs, and failure patterns across thousands of owner reports and technical sources. Learn about our methodology. Always inspect before you buy.