2019-2024 · 2.0L B48 turbo + electric motor · Plug-in hybrid · 292 hp
Modern plug-in hybrid with solid performance and low company car tax. The B48 engine is generally reliable but watch for water pump failures (70,000-100,000 km). The KLE charging module is the Achilles heel - almost all 330e models will eventually need replacement (€1,500-2,500). High voltage battery covered by 8-year/80,000 km warranty, but outside warranty expect €8,000-15,000 for replacement. Electric range drops significantly in winter (22 miles EPA becomes 14-16 miles real-world). Best for drivers who can charge daily and have short commutes.
Almost every 330e will experience this - car won't charge, shows flashing red circle · more· less
This is the most common issue with BMW PHEVs. The KLE (Komfort-Lade-Elektronik) module controls battery charging and typically fails between 3-6 years. Symptoms include "Unable to charge" and "Main power too low" errors, with a flashing red circle on the charging socket. BMW dealer costs range from €2,100-2,500 including labor. Independent shops can replace the unit for around €1,500 total (part costs €1,500, installation is relatively easy with no coding required). Federal law mandates 8-year/100,000-mile warranty coverage on electric vehicle charging components, so check warranty status before paying out of pocket.
High voltage battery degradation/failure€8,000 - €15,500
Battery covered 8 years/80,000 km, expect 10-20% range loss over time · more· less
The 12 kWh lithium-ion battery is covered under BMW's 8-year/80,000 km warranty. Real-world degradation varies - some owners report 50% range loss after 5 years, while others maintain good capacity. Heat accelerates degradation. Battery module replacement costs €4,000 per module (there are 5 modules), with total replacement ranging from €8,000-15,500 including EME (Energy Management Electronics) at €7,500. BMW locks batteries via software making third-party repairs impossible. A 2021 recall addressed loose welding beads causing potential short-circuits. Keep the car on a charger when parked to maximize battery life.
Water pump failure (electric)€600 - €1,400
Common B48 engine issue, typically fails 70,000-100,000 km · more· less
The B48 engine uses an electric water pump integrated with the thermostat housing. The plastic impeller is prone to cracking and the housing can develop leaks. Symptoms include coolant warning light, engine overheating, or poor cabin heating. The integrated part costs €400-500 and labor is approximately 6 hours due to accessibility (total €600-1,400). This is a known issue across BMW's B48/B46 engine family. The pump also cools the turbo after engine shutdown. Consider proactive replacement at 100,000 km to avoid being stranded.
330e has no alternator - 12V charging via DC-DC converter which can fail · more· less
Unlike conventional cars, the 330e has no alternator. The 12V battery (in the boot) is charged through a DC-DC converter from the high voltage battery. When this system fails, the 12V battery drains and the car becomes undrivable. Symptoms include drivetrain errors, "battery not being charged" warnings, and the car protecting itself by disconnecting the HV battery. Sometimes the issue is the KLE module (see above), other times it's the DC-DC converter itself. Diagnosis requires BMW software to check both battery systems. Simple 12V battery replacement costs €200-300, but if DC-DC converter is faulty, expect €800-1,200 for the part and labor.
Oil filter housing gasket/crack leak€400 - €3,100
Plastic housing can crack (coolant leak) or gasket can fail (oil leak) · more· less
The B48 engine has two failure modes here: (1) The plastic oil filter housing itself can crack, leaking coolant. This is more expensive (€2,200-3,100) as it requires removing the intake manifold and replacing the housing - about 9 hours labor. (2) The oil filter housing gasket can fail, leaking oil. This is cheaper (€400-800) but still requires attention. Symptoms include low coolant warnings, oil leaks near the front of the engine, or burning oil smell. Heat and age are the main causes - the gasket hardens and cracks, the plastic housing becomes brittle. If ignored, coolant and oil can mix ("milkshake"), destroying the engine. Regular inspections can catch this early.
Turbo wastegate rattle€1,200 - €2,500
Wastegate actuator develops rattle at low speeds or deceleration · more· less
The turbocharger wastegate controls boost pressure. Over time, the wastegate actuator can develop issues, leading to a rattling noise particularly noticeable at low speeds, idle, or during deceleration. This is a known B48 engine issue. BMW will not sell the actuator separately - you must replace the entire turbo. Actuator-only repair at a specialist costs €500-600 if caught early, but full turbo replacement runs €1,200-2,500. Using premium fuel and regular spirited driving helps prevent carbon buildup in the actuator. Not immediately dangerous but will eventually cause limp mode and EPC warnings.
VANOS solenoid failure€300 - €1,200
Variable valve timing solenoids can fail, causing rough idle and power loss · more· less
The VANOS (Variable Nockenwellensteuerung) system controls valve timing. When solenoids fail, symptoms include sluggish acceleration, loss of power, rough idle, check engine light, and limp mode. The B48 has two VANOS solenoids at €100 each (about 20 minutes DIY replacement). However, if you're paying a shop, labor costs bring the total to €300-1,200 depending on location. Dirty oil or contaminated oil accelerates failure - regular oil changes every 10,000 km are critical. BMW recommends replacing o-rings every 50,000 km as preventive maintenance.
iDrive system freezing/crashing€0 - €2,000
Infotainment system can freeze, lag, or become unresponsive · more· less
The iDrive system controls navigation, entertainment, and climate control. Common issues include freezing, slow boot-up, or complete unresponsiveness. Usually caused by outdated software, corrupted files, or cache buildup. First try a soft reset by holding the iDrive controller down for 25 seconds. If that doesn't work, disconnect the negative battery terminal for 10-15 minutes (hard reset). Regular software updates from BMW often resolve these issues for free. In severe cases where the iDrive unit hardware has failed, replacement costs €1,500-2,000. Check the boot for water ingress under the battery - this can affect iDrive electronics.
Carbon buildup on intake valves€600 - €1,000
Direct injection engines accumulate carbon - walnut blasting needed 80,000 km · more· less
The B48 uses direct fuel injection, spraying fuel directly into the combustion chamber. This means fuel never washes over the intake valves, allowing carbon deposits to accumulate. Symptoms include rough idle, sluggish throttle response, loss of power, and increased fuel consumption. BMW dealers recommend walnut blasting every 80,000 km - a process using compressed air to blast crushed walnut shells into the intake valves to remove carbon without damaging metal parts. Requires removing the intake manifold but not the engine. Dealer cost is around €1,000; independent specialists charge €600-800. Results show noticeable power improvement (10-15 hp) and better throttle response.
Good for a plug-in hybrid, but watch the charging system
The 330e is more reliable than earlier BMW PHEVs, with the B48 engine proving solid. The critical weakness is the KLE charging module - budget for its eventual replacement. High voltage battery has good warranty coverage (8 years/80,000 km). Best ownership experience comes from regular charging and proper maintenance. Avoid if you can't charge regularly - fuel economy drops to 28-38 mpg in hybrid-only mode.
Pre-Purchase Inspection Checklist
General checks
Service history
Complete BMW dealer or specialist records essential. Verify oil changes every 10,000 km.
Cold start
Engine must start completely cold. Listen for unusual sounds, check for smooth operation.
Body condition
Check for rust, accident damage, paint mismatch. G20 is relatively new so rust unlikely.
Test drive
Minimum 30 minutes including varied speeds, electric-only mode, and hybrid mode.
Specific for this vehicle
Test charging functionality
Plug the car in and verify it charges. Check for flashing red circle on charging socket. This is critical - KLE failure is extremely common.
Check electric range display
With full charge, it should show 20-24 miles (or 32-38 km). Significantly lower indicates battery degradation.
Check for coolant leaks
Inspect under the car and around the engine bay for coolant puddles. Check coolant reservoir level. Low coolant = water pump or oil filter housing issues.
Verify high voltage battery warranty status
Check if still under 8-year/80,000 km warranty. This is transferable to new owner. Outside warranty, you're exposed to €8,000-15,000 risk.
12V battery and warning lights
Check for any warnings about battery not charging, drivetrain malfunctions. These indicate DC-DC converter or KLE issues.
Listen for turbo wastegate rattle
At idle and low speeds, listen for rattling from the engine bay. Test in Sport mode with spirited acceleration.
iDrive system operation
Test all iDrive functions - navigation, climate, radio. Check for freezing or slow response.
Regenerative braking feel
Brake pedal should be consistent, not spongy. Some owners don't like the feel - test if acceptable to you.
Check for oil leaks
Inspect around oil filter housing (front of engine) for signs of oil or coolant seepage.
Verify recall completion
2021 models: battery welding bead recall. 2020-2021: rearview camera software. Check with VIN at BMW dealer.
2020-2021: Rearview camera software obstructionVerify completed
2023: Rearview camera image obstructionVerify completed
Contact BMW with VIN to verify all recalls completed. The 2021 battery recall is particularly important - loose welding beads could cause short-circuit. All potentially affected vehicles should have been remedied.
Warranty Status
Factory warranty (4 years/50,000 miles)Expired on most
High voltage battery (8 years/80,000 km)Check VIN - likely active
Federal EV component warranty (8 years/100,000 miles)KLE may qualify
The high voltage battery warranty is the most important - it covers the €8,000-15,000 battery replacement risk. This warranty is not personal; it belongs to the car and transfers to subsequent owners. Federal law in some regions mandates 8-year/100,000-mile warranty on EV batteries and related charging components, potentially covering KLE module failures. Verify exact warranty status with BMW using the VIN before purchase.
This report is for informational purposes only and does not constitute professional advice. Estimates may be inaccurate. Always have a qualified specialist inspect the vehicle before purchase. We accept no liability for decisions made based on this information.