2017 BMW 3 Series

Sold as 320i, 320i xDrive, 328d, 328d xDrive, 340i, 340i xDrive, 330i, 330i xDrive, 330e

This page is a draft. It has not been approved yet, so read it with care.

Watch out for

Reputation: what owners and the press report. Tap one to see what to check.

Timing chain stretch on the N20 four All years

What to check: Listen for a whine or rattle at a cold start and idle, and ask whether the timing chain, guides and tensioner were replaced with updated parts.

AutoTrader.ca reports owners of 2012–2014 328is with stretched or failed chains, some losing the engine. Euro Premium Parts says the stretch can break the plastic guides. In one owner forum thread two owners describe a whine after a cold start, a third says a whine comes before failure, and a poster who works at a dealer says many early N20s got new engines. In another, two owners report original chains still fine at about 134,000 miles, and one found the old parts in good order when replacing them at 132,000.

Sources ^1,2,3,4
Oil leaks on the N55 six All years One source so far

What to check: Look for oil around the valve cover, the oil filter housing and the oil pan.

Euro Premium Parts lists leaks from these gaskets on the N55, and carbon on the intake valves of cars driven mostly in town.

Sources ²
Coolant leaks on the newer four All years One source so far

What to check: Look for coolant at the upper radiator hose and the oil filter housing.

Euro Premium Parts reports occasional leaks at these two points, cheap to fix.

Sources ²
Automatic gearbox fluid leak All years One source so far

What to check: Look under the gearbox for fluid, where the wiring plug enters it.

AutoTrader.ca says a failed seal at the gearbox's electrical connector can leak fluid, and that leaving it can damage the gearbox.

Sources ¹
iDrive glitches and failed lights All years One source so far

What to check: Try the screen, phone pairing, navigation and reversing camera, and check every headlight and tail light.

AutoTrader.ca reports owners with iDrive crashing or lagging, and with failed LED tail lights, and says xenon and LED headlights are costly to replace.

Sources ¹
Airbag warning light All years One source so far

What to check: Make sure the airbag light goes out after starting.

AutoTrader.ca says some owners blame a faulty seat sensor, often replaced under warranty, and advises having any airbag light fixed before buying.

Sources ¹

Recalls

18V755000 2014–2018
A leaking exhaust gas recirculation cooler can let coolant mix with soot, which can melt the intake manifold and start a fire. Widened by 21V907000.⁵
21V586000 2014–2018
The diesel's high-pressure fuel pump can fail and stall the engine while driving.⁵
21V907000 2014–2018
More cars and a further fix for the exhaust gas recirculation cooler leak in 18V755000.⁵

Watch out for

Recalls

Sources