The E90 320i is the entry-level petrol in the fifth-generation 3 Series, powered by the 2.0-litre N46B20 four-cylinder producing 150 hp. Sold across Europe from 2005 to 2007 in pre-LCI form (some markets continued the N46 into the LCI phase where fuel quality prevented use of the N43 replacement). It offers a decent balance of BMW driving dynamics and reasonable fuel economy, though the N46 engine has a mixed reliability reputation compared to BMW's inline-six family.· more· less
Affordable BMW 3 Series ownershipGood parts availability, large community
N46 Valvetronic system failure-proneMultiple oil leak points with age
Buy if: You want an affordable rear-wheel-drive BMW and can find one with documented service history and no cold-start rattle.
Avoid if: You hear timing chain rattle on cold start, the service history is incomplete, or you need a trouble-free daily driver on a tight budget.
Price & maintenance
Used price
€4,500
median asking price, typically 190,000 km
Typical range€3,000 – €6,300
Kilometres drivenAll
Maintenance cost
€800 – €1,550/year
at 15,000 km/year
Fixed costsservice, tyres, brakes€450 – €750 /yr
Risk bufferunplanned repairs€350 – €800 /yr
Price estimates are based on German asking prices. Prices and costs vary by vehicle condition and location.
Ownership costs
Maintenance assumes 15,000 km a year. Price estimates are based on German asking prices. Prices and costs vary by vehicle condition and location.
Used price
€4,500
Typically €3,000 – €6,300, at around 190,000 km.
Kilometres driven
Maintenance
€800 – €1,550per year
€450 – €750
service, tyres, brakes
€350 – €800
repair buffer
Price & maintenance
Used price
€6,500
median asking price, typically 190,000 km
Typical range€4,700 – €8,500
Kilometres drivenAll
Maintenance cost
€800 – €1,550/year
at 15,000 km/year
Fixed costsservice, tyres, brakes€450 – €750 /yr
Risk bufferunplanned repairs€350 – €800 /yr
Price estimates are based on French asking prices. Prices and costs vary by vehicle condition and location.
Ownership costs
Maintenance assumes 15,000 km a year. Price estimates are based on French asking prices. Prices and costs vary by vehicle condition and location.
Chain stretches and tensioner bleeds down overnight, causing cold-start rattle · more· less
The N46 engine uses a timing chain with a hydraulic tensioner that can lose oil pressure overnight as the release valve weakens. This causes a distinctive rattle during the first few seconds after a cold start. The issue typically develops between 80,000 and 130,000 km. If the rattle lasts more than a few seconds, the chain, guides, tensioner, and sprockets all need replacing. BMW released an updated tensioner part number. At an independent BMW specialist, expect €1,000-1,500 for the full replacement. BMW dealers quote €1,500-2,200. Ignoring the rattle risks the chain skipping teeth, which causes valve-piston contact and catastrophic engine damage.
Valvetronic eccentric shaft sensor failure
up to €1,5002 of 6
Oil seeps through the sensor connector, causing valvetronic faults and rough running · more· less
The N46 uses BMW's Valvetronic system with an eccentric shaft sensor mounted behind the oil filler cap. Over time, oil migrates through the sensor seal and fills the electrical connector, causing sensor faults. Symptoms include check engine light, rough idle, and reduced power. The sensor itself costs around €80-120, but the repair often requires replacing the valve cover gasket at the same time and is labour-intensive (3-4 hours). Total cost at an independent shop runs €400-800, or €800-1,500 at a dealer. If the eccentric shaft itself has been damaged from prolonged driving with a faulty sensor, the repair escalates significantly.
Valvetronic motor failure
up to €2,0003 of 6
Electric motor that controls valve lift fails, causing limp mode and loss of power · more· less
The Valvetronic motor adjusts intake valve lift continuously. When it fails, the engine enters a default mode with limited power output and a check engine light. The motor costs approximately €250-400 for the part. Labor is 2-3 hours at an independent shop, bringing the total to €600-1,000. At a BMW dealer, expect €1,200-2,000. The motor tends to fail more often on cars that have been driven with a leaking eccentric shaft sensor for an extended period, as the electrical issues compound.
Multiple gasket seals degrade with age, causing oil weeping from several locations · more· less
The N46 is known for developing oil leaks from multiple locations as gaskets age. The three most common sources are the valve cover gasket (€300-500 at an independent shop), the oil filter housing gasket (€250-400), and the vacuum pump seal (€200-400). The vacuum pump in particular is a well-documented N46 weak point, with the internal diaphragm degrading and allowing oil to seep past. Many E90 320i owners end up addressing all three leak points within a few years of each other, typically after 100,000 km. If all are done simultaneously, expect €800-1,500 in total. Left unaddressed, oil can drip onto hot exhaust components or contaminate the cooling system.
Window regulator failure
up to €5005 of 6
Plastic clips and cable mechanism break, causing windows to drop or stick · more· less
Failed window regulators are a widespread E90 issue. The plastic clips that hold the cable mechanism break, causing the window to drop into the door or move very slowly. Rear windows are affected more often than fronts. A replacement regulator costs €80-150 for the part, with about 1-2 hours of labour. Total repair at an independent shop runs €200-350, or €350-500 at a dealer. Repair clips are available as a cheaper temporary fix (€15-30) but the full regulator replacement is the lasting solution.
Interior trim coating degradation
up to €5006 of 6
Rubberized soft-touch coating on door handles and trim becomes sticky and peels · more· less
The E90 uses a rubberized soft-touch coating on interior door pull handles and various trim pieces that degrades over time from heat, UV exposure, and skin oils. The coating becomes sticky, then starts peeling. This is a cosmetic issue that affects virtually all E90s over 10 years old. BMW dealer replacement of all four door handles costs €500+. Aftermarket replacement handles are available for €30-60 each. Refinishing services or vinyl wrapping offer cheaper alternatives at €100-200 for the entire set.
Moderate reliability, several known weak points
The N46 engine is functional but not among BMW's best. The Valvetronic system, timing chain tensioner, and multiple oil leak points are well-documented problem areas. With proactive maintenance and prompt attention to warning signs (especially cold-start rattle and oil leaks), the 320i E90 can provide reasonable service beyond 200,000 km. However, deferred maintenance quickly escalates costs. Manual gearbox models are more reliable overall.
Service history
Complete BMW dealer or specialist records essential. Verify oil changes every 12 months or 15,000 km maximum.
Tires
Check tread depth, age (date codes on sidewall), and uneven wear patterns indicating suspension issues.
Cold start
Must start engine completely cold. Listen carefully for any rattle or unusual noise in the first 30 seconds.
Test drive
Minimum 20 minutes including varied speeds. Check for smooth gear changes, steady idle, and no warning lights.
Specific for this vehicle
Listen for timing chain rattle on cold start
Start the engine completely cold and listen for rattle in the first 5-30 seconds. Any persistent rattle indicates chain and tensioner wear requiring immediate attention.
Check for oil leaks underneath and around engine
Look for oil residue around the valve cover, oil filter housing (front of engine), and vacuum pump area. Multiple leak points are common on higher-mileage cars.
Test Valvetronic system operation
Watch for check engine light, rough idle, or hesitation on acceleration. These can indicate eccentric shaft sensor or Valvetronic motor faults.
+ 3 more checksShow less
Inspect interior door handle trim
Run your fingers over the door pull handles and centre console trim. Sticky or peeling coating is cosmetic but indicates the car's age-related condition.
Test all four windows
Operate all windows up and down fully. Listen for grinding or clicking from the door panels, and watch for slow or jerky movement.
Verify blower motor recall completed
The heater fan regulator fire risk recall affects all E90s built July 2004 to June 2012. Contact BMW with VIN to confirm.
Recalls and Technical Service Bulletins
Heater blower fan regulator fire risk (Germany: production Jul 2004 - Jun 2012; UK: Dec 2004 - Jul 2011)Critical - verify completed
Battery cable connector (B+) degradation causing engine cutout (UK: production Mar 2007 - Sep 2011)Verify completed
Original driver airbag inflator, Finnish campaign 0032520300 for E90/E91Verify with BMW using VIN
Replacement Sport or M Sport steering wheel airbag, campaign 0032570300Verify with BMW using VIN
The heater blower fan regulator recall is particularly important as it poses a fire risk even when parked, and its build window differs by country, so ask BMW for the scope that applies where the car was sold. The two airbag campaigns are separate: one covers the original driver airbag, the other a replacement Sport or M Sport wheel. Contact BMW with the VIN to verify all of them.
Warranty Status
Factory warranty (2 years, 3 years in the UK)Expired on all E90 320i models
Rust perforation warranty (12 years)Expired on all pre-2014 production
All BMW E90 320i models are well outside their original factory warranty, which was two years in most of Europe and three years in the UK from 2004. Third-party extended warranties are available but check exclusions carefully, as pre-existing oil leaks and Valvetronic issues are often excluded.
Sources: Research draws on model-specific owner forums and owner communities, recall information from official authorities, German automotive press, and multiple workshop cost references cross-checked against each other.
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.
