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2018 BMW 340I problems

The most common problem on the 2018 BMW 340I is engine and cooling. It has fewer complaints than a typical 340I model year.

Typical yearClose to a typical year
Owner complaints
3
Recalls
1
Service bulletins
801 warranty
Worst area
Engine

The worst 2018 BMW 340I problems

Ranked by number of owner complaints. Mileage and cost come from what owners wrote.

  • Engine
    2
  • Fuel system
    1

Problems by type

Tap a problem to see which part fails, at what mileage and in which other years.

  • Engine
    2
  • Fuel system
    1

Recalls 1

Engine and engine cooling: engineReported July 11, 2018 · 5,309 vehicles affected
What is wrong
BMW of North America, LLC (BMW) is recalling certain 2018 BMW 540d xDrive vehicles. The crankshaft sensor may be equipped with incorrect firmware, preventing the sensor from properly processing input from the crankshaft reluctor ring, possibly resulting in a vehicle stall. On September 12, 2018, BMW expanded the recall to a total of 5,309 vehicles including certain 2018-2019 BMW 540d xDrive, 230i M240i, M240i xDrive, X2 sDrive28i, X2 xDrive28i, X1 sDrive28i, X1 xDrive28i, 330i, 330i xDrive, 340i, 340i xDrive, 330i xDrive Gran Turismo, 530i, 530i xDrive, 540i, 540i xDrive, 530e, 530e xDrive, 640i xDrive Gran Turismo, 330e, 2019 430i Gran Coupe, 430i xDrive Gran Coupe, 440i Gran Coupe, 440i xDrive Gran Coupe, 430i, 430i xDrive, 440i, 440i xDrive, 740i, 740i xDrive, MINI Cooper, Cooper S, JCW, MINI Countryman (Cooper, Cooper All4, Cooper S, Cooper S All4, JCW All4), and MINI Clubman (Cooper, Cooper S, Cooper All4, Cooper S All4, JCW All4) vehicles.
Risk
A vehicle stall can increase the risk of a crash.
Remedy
BMW will notify owners, and dealers will replace the crankshaft sensor, free of charge. The recall began September 6, 2018. Owners may contact BMW customer service at 1‑800‑525‑7417.

Recall number 18V465000 · Recall details

See all 1 recalls for the 2018 BMW 340I

Defect investigations

Desiccated Air Bag Inflator RuptureOpened September 17, 2021, still open

From 2000 through 2017, Takata produced millions of air bag inflators using two types of phase-stabilized ammonium nitrate ("PSAN") propellant -- propellant 2004 and propellant 2004L. After prolonged exposure to high temperature cycles and humidity, inflators using propellant 2004 can degrade, causing the propellant to burn too quickly when ignited. The rapid burning can cause the inflator to rupture during deployment, potentially causing serious or even fatal injury to vehicle occupants. See 2016 Blomquist Report at all frontal inflators using propellant 2004 that do not contain a "desiccant" (a substance that traps and holds moisture) in US vehicles are under recall. These "non-desiccated" inflators either have been or are required to be replaced.In some cases, the remedy part for these recalled inflators was, or will be, an inflator using either propellant 2004 or 2004L that does contain a desiccant. None of these "desiccated" remedy parts (which were installed in older model year vehicles) are currently under recall for a degradation concern. Certain subsets of desiccated PSAN inflators using propellant 2004 for use as original equipment, however, have been recalled for a degradation concern. All Takata inflators produced with propellant 2004L contain desiccant, and none of these desiccated inflators using propellant 2004L are under recall for a degradation concern. There have been no reported field ruptures in any non-recalled desiccated PSAN inflators.It is understood that desiccants fully saturate at some threshold, at which point any additional moisture will not be captured. This means the degradation process observed in non-desiccated inflators using propellant 2004 may also occur in non-recalled desiccated inflators using propellant 2004, assuming additional moisture enters the inflator and high temperature cycling occurs. Based on available information, desiccant saturation can occur within the first five years in the worst environments, and the time required for full saturation is affected by multiple factors. While no present safety risk has been identified, further work is needed to evaluate the future risk of non-recalled desiccated inflators using propellant 2004.Three entities -- Takata (now known as TK Global), the Independent Testing Coalition, and Exponent -- have been studying the long-term behavior of Takata desiccated PSAN inflators using propellant 2004L (as well as 2004) in the presence of moisture and temperature cycling. The research efforts, which include development of predictive modeling techniques and field sample analysis, are ongoing. To date, none of the researchers have identified field evidence showing that propellant 2004L is undergoing a degradation process that leads to aggressive deployment and potential rupture. However, the time in service of such inflators remains short compared to that of the inflators using propellant 2004. Further study is needed to assess the long-term safety of desiccated inflators using propellant 2004L.The Office of Defects Investigation is opening this investigation to examine whether a safety defect related to propellant degradation exists in non-recalled desiccated PSAN frontal inflators manufactured by Takata. This investigation will require extensive information on Takata production processes and surveys of inflators in the field. Lists of recall actions that may have used desiccated PSAN inflators as remedy parts, as well as the makes and models originally manufactured with them, is available with the downloadable version of this document (see -- note this information is subject to change/revision as the investigation proceeds). This investigation does not supersede EA15-001, which remains open.

EA21002

Technical service bulletins for the 2018 BMW 340I 80

Bulletins tell dealers how to fix known problems. A warranty extension means the manufacturer pays for that repair for longer.

See all 80 bulletins for the 2018 BMW 340I

What 2018 BMW 340I owners say

Most recent owner complaints, unedited.

Filed Oct 26, 2023 · Engine · TX

The radiator failed due to rocks flying through the grill and smashing the radiator causing coolant to flow out of the radiator which could cause deadly issues if a car has no coolant while operating. Bmw knows this is an issue and refuses to warranty/recall the parts. They know its an issue because after 12/17 every 340i came with a rock guard to protect the radiator but every car before that was just left to be victim of a potentially deadly situation including mine (manufactured 10/17). Bmw refuses to acknowledge the problem but the addition of the rock guard to cars after 12/17 should be enough evidence to show they knew it was an issue. Now all 2016-2018 m sport f30 chassis built before 12/7 are susceptible to this deadly situation and bmw refuses to cover for any damages even though they know it's a serious issue and they won't even cover the rock guard

Filed Apr 22, 2023 · Fuel system · CO

Fuel Tank Filler Hose Collapse - unable to refuel and vehicle remains stranded.

Filed Mar 8, 2021 · Engine · 20,000 miles · CA · fire

Returning from a local grocery store I drove into our garage and shut off the engine. Immediately I heard a loud pop from the engine compartment, like from a firecracker, and I saw black smoke coming from the hood and from the left wheel well. I immediately tried to restart the car to drive out of the garage. Nothing worked so I pushed the car out of the garage by hand and released the hood latch. By now the hood's external safety latch was so hot I could not release it. With the hood closed, I was unable to extinguish the engine fire using a 15 lb co2 and a 5 lb abc extinguisher. The city fire department also were unable to extinguish the fire until they sawed the hood in half. The 2 1/2 year old car was a total loss. A expert from bmw of north america inspected the car reporting that was too much damage to determine the fire's cause. Bmw na called to report the result not their investigation and say that no written report was available, only the verbal verbal fonecon.

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Questions about the 2018 BMW 340I

Is the 2018 BMW 340I reliable?

Owners have filed 3 complaints about the 2018 BMW 340I, fewer than a typical 340I model year.

What is the most common problem with the 2018 BMW 340I?

Engine and cooling, with 2 complaints. Next is fuel system (1).

How many recalls does the 2018 BMW 340I have?

1 recall, covering engine and engine cooling.

Was there a recall on the 2018 BMW 340I engine?

Yes, 1 recall: 18V465000. Check your VIN to see if your car still needs the free repair.

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