12 Common BMW 4 Series Problems (Explained)

BMW started calling the 2-door variants of the iconic 3-Series as the 4-Series in 2014.

Although it’s almost the same as the 3-Series, the 4-Series tends to be sportier and more expensive overall.

In this article, we’ll take a look at some of the common problems and issues owners have encountered with the BMW 4-Series through the years.

1. Timing Chain Failures

Early models of the BMW 428i which used the 4-cylinder N20 engine can suffer from timing chain issues.

The timing chain can show premature wear and even break without any symptoms at 50,000 to 100,000 miles.

This problem typically only affects the 2014 and early 2015 models. It’s also a lot more common in older BMW models fitted with the N20 engine.

Cars built after February 2015 replaced the plastic timing chain guide which wore out quickly with longer lasting parts.

The N47 diesel engine used in other markets around the world has also had a history of timing chain issues.

Premature failures of the timing chain tensioner and the plastic chain guides often led to:

• Play/slack in the timing chain
• Timing chain skipping teeth/gears
• Broken bits falling into oil pan

When the timing chain breaks, it usually leads to catastrophic engine damage.

Symptoms of N20 timing chain issues include:

• Whining noise when revving engine
• Engine rattle
• ‘Drivetrain Malfunction’ error
• Low oil pressure warning
• Misfires 

Here’s what two users on the BimmerPost.com forum had to say:

“I have had 2 BMW’s both with N20 engines, and this issue plagued both vehicles. They both had the TC whine, but my F30 got into a car accident and was totaled out before it could be addressed.”

“My mechanic quoted me $800 for labor and it was done about a month ago on my f36 n20. He also charged me $250 extra for a new oil pan and OFHG so in total, $1050.”

BMW did extend the warranty for the timing chain on affected models to 7 years or 70,000 miles.

Replacing the timing chain and chain guides with the updated BMW parts should prevent future problems from occurring, but this can cost you around $1,000 to $2,000.

2. Leaking Valve Cover Gasket 

Oil leaks caused by a bad valve cover gasket is a very common issue in a lot of modern BMWs.

BMWs are notorious for developing oil leaks as they get older and the engine’s seals and gaskets wear out.

The first gasket that usually goes out in newer BMW engines is the valve cover gasket.

The plastic valve cover can also warp or crack which also results in oil leaks.

Valve cover oil leaks can occur in pretty much every model year of the BMW 4-Series starting from 2014 up to the latest ones.

Reports are more common in the N20 and N55 powered models because they’re several years old by now, but even the newer generation with the B48 and B58 engines are not completely immune.

Symptoms of a faulty valve cover gasket include:

• Burnt oil smell
• Smoking around valve cover
• Oil on spark plugs
• Low oil warning 

Here’s are a couple of owner experiences from the BimmerPost.com forum:

“MY2016 F36 VCG got replace at 27k… service saw some oil outside.”

“My valve cover failed in the same spot. I would get puffs of smoke and a bad smell when it hit the exhaust. My car had ~80k miles at the point of replacement.”

“I’ve just had some maintenance work done on my 435i and found out that there is a leak coming from the valve cover gasket. The car just hit the 60k mark and is a 2015 model.”

In most cases, the oil leak from the valve cover is very small and doesn’t really completely drain out the oil from the engine.

Replacing the valve cover gasket shouldn’t be too expensive and any reputable mechanic should be able to finish the job in an hour or so. 

A new OEM valve cover is more expensive at around $500, but it’s still a fairly easy fix for any experienced mechanic.

3. PCV Issues

Another common issue that can affect a higher mileage 4-Series is a torn PCV valve.

This problem typically affects the 2014 to 2019 model years of the 4-Series which includes the 428i, 435i, and early years of the 440i.

The PCV (Positive Crankcase Ventilation) system improves the engine’s emissions by recirculating blow-by gasses back into the engine so it can burn up and not just vented into the atmosphere.

One of the PCV system’s valves is a rubber diaphragm that can wear out and break over time.

This valve regulates the amount of pressure in the crankcase. When it breaks, the engine will have excess buildup of pressure

Common symptoms of a faulty PCV valve include:

• White smoke from exhaust
• Howling, whistling or squealing noise when idling
• Leaking front or rear main seal

These problems are also common in a lot of modern turbocharged BMWs, so it’s not just unique to the 4-Series.

Here’s a 2018 440i owner’s experience on BimmerPost.com:

“My car experienced a loud whistling sound followed by white smoke coming from my tailpipe on Christmas Eve and I assumed it was due to my PCV diaphragm failing.” 

The faulty PCV valve is integrated into the valve cover. Normally, dealers will simply replace the entire valve cover to fix the PCV issues.

Due to the number of failures, some companies have released aftermarket PCV replacement kits, as well as PCV delete kits.

Related: 10 Best & Worst BMW 4-Series Years (With Facts & Stats)

4. Leaking Oil Filter Housing Gasket

Another common oil leak that affects the first generation of the BMW 4-Series comes from the oil filter housing gasket.

This issue affects the 2014 to 2016 model years of the 428i and 435i which used BMW’s N20 and N55 engines.

It also affects the 2015 to 2020 model years of the BMW M4 which uses the S55 engine.

Here’s what two 435i owners had to say on BimmerPost.com: 

“I currently have 104,000 miles on mine and the only problem I’ve had is the oil filter housing gasket leaking at around 50,000 miles.”

“My 2014 435i (46K miles) just went in for service and service advisor alerted me to an oil leak before I saw any evidence. The leak came from the full-flow filter body (aka, oil filter housing) and fixed under warranty. Per my advisor, this is becoming more common now that they are starting to see high-mileage. They also noticed “cold-climate” vehicles develop this issue at a higher mileage than “hot-climate” vehicles.”

A new oil filter housing gasket costs only a few dollars, but labor can add a few hundred dollars.

If the plastic oil filter housing itself is cracked, the parts will cost several hundred dollars and the install is significantly more labor intensive.

If you already know there’s a leak but can’t get it fixed right away, you’ll need to regularly check the oil level and top it up if it’s a bit low.

5. Blown Charge Pipe

A common issue with many N20 and N55 powered BMWs is the charge pipe that connects to the throttle body and intercooler breaking at relatively low miles.

The charge pipe is made of plastic and can eventually break apart in just a few years, especially if the car has been modified for more boost and power.

But charge pipe failures have also been fairly common even in cars that are completely stock.

This particular problem tends to affect the higher powered N55 and S55 engines found in the 435i and M4.

The BMW 435i was only sold for the 2014 to 2016 model years while the S55 powered BMW M4 went on until 2020.

Symptoms of a blown charge pipe include:

• Lack of power
• No boost
• Service engine soon error
• Drivetrain malfunction warning
• Check engine light
• Loud pop sound 

Here’s how a few owners described their experience on BimmerPost.com

“I blew my charge pipe yesterday on my 2016 435i. Need some advice on whether to take it to the dealer to be replaced or just order an upgrade like the VRSF and get it replaced. My car is still covered under warranty until December. Is this covered under that? I know it’s common for these to go bad and highly recommended to replace these, but weighing my options on the best route to go.”

“Got a 2015 435i 55k stock that had a drive train malfunction on the highway. Drove it about 4 mi then had it towed to the house. Popped the hood and discovered charge pipe broken. Got a new charge pipe on the way. Every time I start the engine it’s shaking pretty bad and stalls.”

OEM or aftermarket charge pipe costs around $200 to $400, and many enthusiasts typically go for aftermarket ones made out of metal.

Installing the new charge pipe shouldn’t be too difficult since it’s usually connected using clamps.

Tuning and modding will also require a charge pipe upgrade as the power output goes up.

6. Leaking Plastic Cooling Parts

Like most BMWs, the 4-Series uses a lot of plastic for its cooling system which can get brittle and fail in just a few years.

The coolant expansion tank hose is one of the most common things that breaks and causes a large coolant leak in the 4-Series, as well as other BMWs equipped with the N55 engine.  

Other cooling components that you’ll want to keep an eye on include:

• Hoses and pipes
• Expansion tank hose
• Reservoir
• Parts of the radiator

In most cases, you’ll get a low coolant warning on the dash before any major failures.

Here’s how a few 4-Series owners described their experience:

“I got a 2015 435i Coupe (F32). There are two hoses that run parallel to each other and sit above the radiator. One is a Coolant Expansion Tank Vent/Hose which has become a known pain point on these cars and often crack between 50-90k. Mine had this issue and was just replaced.” 

“Right after I parked my car in the garage and turned off the engine, I heard a pop then I saw steam coming up from under the hood and what looks to be coolant pooling under my car. I followed the line from the reservoir and I find that the hose/pipe just busted off and all the coolant from the reservoir was just spilling into my engine bay then onto the ground.”

“My connector just broke off as well. Sorry I didn’t see this thread before it happened. 2014 f32 with 80K.”

Once the car nears the 10-year mark, you’re going to see more and more cooling system component failures.

It’s a good idea to routinely check the coolant levels every few months and not wait for the low coolant warning to appear if you want to keep your engine in great condition. 

If the engine overheats, pull over and have it towed to avoid damaging it further.

7. Water Pump Failure

Water pumps in lots of modern BMWs tend to start failing between 50,000 to 100,000 miles. 

BMW’s early turbo engines like the N54 had lots of premature water pump failures and it can still be an issue even in newer cars, but to a lesser extent.

Water pump issues are still fairly common with the newer N20, N55 and S55 engines used in the 4-Series, as well as with the newer B48 and B58 engines.

The thermostat is also a common weak point and can get stuck open or closed at around the same time the water pump goes. 

Some signs that might tell you that the electric water pump is problematic include: 

• Cooling fan constantly runs at high speed
• Engine temperature warning on the dash
• Trouble code for 2e83 or “electrical cooling pump, low power mode”
• Water pump runs all the time
• Constant battery drain
• Coolant leaks

Here is how a few 4-Series owners on the Bimmerfest.com forum described their experience:

“The water pump in my 2016 435i went out at 57,000 miles.”

“Water pump constantly running – 2014 435i. Initially began with a failed no start. Got new battery. Car ran fine for 3 weeks until it didn’t start late January. Upon connecting my jump box, electric water pump instantly engaged. Anyone have any idea on the wiring diagram for the water pump? Now, it sometimes stays on and sometimes doesn’t. I never know when its going to drain my battery.”

If you see a temperature warning on the dash, it’s best to pull over and let the engine cool down for around 30 minutes before driving off again. This will help prevent catastrophic engine damage.

Once you start experiencing symptoms of a failing water pump, you’ll want to swap it out for a new OEM unit before it stops working altogether. 

A new water pump costs around $400 and installation is typically about the same.

When replacing the water pump, most people also install a new thermostat at the same time to avoid having to tear into the engine bay again.

8. Fuel Pump Recall

Early models of the 4-Series were part of a pretty large recall that BMW issued to address faulty fuel pumps.

This recall only affects the 2014 to 2015 model years of the 428i and 435i models.

When the fuel pump starts acting up, you encounter symptoms such as:

• Hard starting
• Intermittent stalling
• Misfires
• Hesitation
• Reduced power or stalling
• ‘Drivetrain Malfunction’ error

Here’s what a few 4-Series owners had to say on the BimmerPost.com forum:

I am based in the UK and have a 2013 BMW F32 428i that has less than 23k miles. The car broke down on the Motorway and suffered the infamous ‘Drivetrain Failure’ limp mode issue whilst driving.

The local BMW dealer has diagnosed the problem to be a failed Fuel pump and says that the whole Fuel tank needs to be replaced.

 I picked up my new 428i last week and couldn’t be happier with the car. Love the color combo (MG/CR) and handles great. However, after less than 96 hours of having the car and 100 miles later, it shut down on me while I was pulling out of the garage. It would crank and crank but the engine wouldn’t turn over.

“A friend of ours who just picked up her 428ix Coupe a few weeks ago was driving when the engine shook and then just died in the middle of the road.”

If your car hasn’t had the recall done yet, it’s best to take it back to the dealer to check if it can still be performed free of charge.

Once the recall is performed, you should have the updated part and have no more issues in the future.

Fuel pump failures can still occur as the mileage goes up and the pumps internal components wear out after several years.

A new OEM fuel pump costs around $300 and usually needs to be replaced every 100,000 to 200,000 miles.

9. DCT Issues

Many owners of the first gen F82 and F83 BMW M4 have noticed that the dual clutch transmission (DCT) needs some time before it actually shifts into reverse.

After selecting reverse and stepping on the gas, the DCT can feel like it’s still in neutral even if the dash says it’s already in reverse.

This issue typically occurs after the vehicle has been sitting for a while and can be intermittent.

It’s only been reported for the first generation M4 which was sold from 2015 to 2020.

Here’s how a few owners described their experience:

“I recently got my 2017 M4 ZCP and I am enjoying it. This is my first DCT vehicle. One thing I noticed about the DCT is that it has significant delay when shifting from P to D, or R to D, compared to my previous M235’s ZF8 tranny.”

“My GTS on two occasions now won’t go into reverse and the car won’t throw a fault code and BMW says there is nothing wrong with the car despite having videos. The shifter is in reverse but the car is in neutral and the N blinks.”

The delayed shifting doesn’t necessarily mean there’s an issue with the transmission and the car will eventually go into reverse. 

You just need to wait a few seconds after starting the car before trying to shift it into reverse.

Many have also reported that they hear a soft clunking noise when shifting into reverse, but this is normal for the M4’s DCT.

10. Vibration from Steering Wheel

Some older examples of the BMW 4-Series have a slight vibration from the steering wheel when traveling at highway speeds.

This is also a fairly common complaint among owners of the sixth generation 3-Series, which is just the sedan equivalent of the 4-Series.

The problem can occur in vehicles that are relatively brand new, as well as cars with really high miles.

Here’s what a few owners on BimmerPost.com had to say:

“I just had a 428 sportline as loaner for 2 days. (4000 miles). It had minor steering wheel vibration too, feels just like my F30.”

“My 428 does this. My wheels have been road force balanced, and I can see no visible shimmy in the wheel, but if I grip the wheel when I’m driving I can feel a little vibrating in the palm of my hands.”

“I’m having this issue with my 16 428i Gran Coupe. All 4 tires are RFB, alignment is good, wheels were inspected/tested for damage and they came back clean. The steering wheel just shimmies between 40-60 mph…it’s driving me insane because it’s inconsistent.” 

The most common cause of the vibration is improper tire balancing. 

Getting all four wheels road force balanced and/or getting new tires is the most common fix for the steering vibration.

In some cases, the problem is caused by a faulty steering column which is going to be more expensive to repair out of warranty. 

11. Spun Crank Hub

A small number of BMW M4 owners have had engine failures caused by a spun crank hub. 

The crank hub is attached to the crankshaft and helps keep proper timing of the engine. 

When it spins, the car will have all sorts of drivability issues and it can even warrant an engine replacement.

Spun crank hubs are more common in DCT equipped cars from the 2015 model year, but it’s also been reported in newer cars up to the 2018 model year.

Failures are more likely to occur in modified vehicles that produce over 500 hp, but a very small percentage of stock cars have also had crank hub issues.

This issue also affects the S55 powered M3 and M2 Competition.

Symptoms of a spun crank hub include:

• Limp mode
• Drivetrain Malfunction warning
• Hard starting
• Rough idling
• Check engine light
• Timing and VANOS related trouble codes

Here’s one M4 owner’s experience: 

“Car has 12,000 miles and is a MY15 M4 with DCT. I was driving moderately last night and a Drivetrain Malfunction and Reduced Power warning screen showed up. The technician said that it was definitely a spun crank hub, but it wasn’t very bad. Remedy will be replace crank bolt and retime engine.”

“The past 3 months, I have noticed that the car takes extra cranks to start. When the car showed the malfunction, I was still able to drive home. When I was driving home, I pulled off to the shoulder and restarted the car. The car ran normal with full power for about 200 yards then the malfunction showed up again.”

If the crank hub spins, it usually just needs to be replaced and the timing has to be corrected. The cost for this repair costs around $2,000.  

If the failure occurs when the engine is working hard, the damage can be more catastrophic and can cost several thousand dollars to fix.

Owners of modified BMW M4s usually install aftermarket kits that help prevent the issue like a crank bolt capture (CBC) kit or a keyed crank hub that locks the hub into the crankshaft. 

12. VANOS Solenoid Issues

BMW’s VANOS variable timing system has always been a major maintenance item since it was first used in the mid 1990s.

Newer VANOS systems found in the 4-Series can still fail but they are much easier to fix.

In most cases, it’s usually just the VANOS solenoid that’s faulty and can be easily replaced without having to rebuild the entire VANOS unit.

Symptoms of VANOS related issues include:

• Limp mode
• Lack of power/hesitation
• Rough idle
• Lower gas mileage
• Rattling sound
• Check engine light

Here’s how one owner described their experience:

“When I took my basically new still 428i with just 39,000km out of covid storage, there was a lot of rough idling and stalls, i used bimmerlink and got a whole bunch of random codes (see code photos below) so with the help of a friend who was a senior technician at bmw dealership, we found the culprit to be the VANOS solenoid actuator.” 

Each of the two VANOS solenoids cost around $150 a piece plus a few hundred dollars in labor.

In the newer B48 and B58 engines, the solenoids were moved to the back of the engine which makes replacement much more difficult.

If you suspect that you’re having VANOS related issues, it’s best to have it diagnosed by a dealer or an independent garage that specializes in BMWs.

In a lot of cases, simply cleaning out the VANOS solenoids can also get rid of the running and drivablility issues.

Related: 10 Most Common BMW 3-Series Problems (Explained)

BMW 4-Series Pros & Cons

Pros

• Excellent handling
• Refined and luxurious interior
• Good ride comfort
• Several powertrain options
• Lots of cutting edge tech
• Packed with features and creature comforts
• Great reliability

Cons

• Cramped rear seats
• More noise and rattles than 3-Series
• Expensive 
• Costly maintenance

What Do The Reviews Say?

“The distinctive grille of the 4 Series might make you consider another car, but if the design doesn’t bother you, the 4 Series is a compelling choice. It delivers an engaging driving experience without sacrificing comfort, and it provides plenty of luxury and tech.”

“We tested a rear-wheel-drive M440i convertible. It packs a lot of punch, and in our testing it ripped from 0 to 60 mph in 4.6 seconds — a full second quicker than a similarly equipped 430i coupe we also tested.”

“The steering is a little vague during truly spirited driving. It’s a mild disappointment in a BMW, though the reality is that rivals aren’t appreciably better in this regard. Handling is a 4 Series strength, with stable composure around tight bends and a seemingly high limit for traction control intervention. The eight-speed automatic shifts smoothly and always seems to be in the right gear, making this an easy car to live with.”

“The M440i’s standard adaptive suspension provides a surprisingly supple ride. Wind and tire noise is kept to a minimum too.” 

“There’s decent legroom up front, but the compact dimensions limit the usefulness of the rear seat.”

“The smooth inline-six of the M440i is a great motor. The thrust is palpable, and the exhaust note is throaty and burbly. The thing is, the 430i isn’t that much slower and saves you about $10,000.”

2023 BMW 4-Series | Edmunds

What’s the Resale Value of a BMW 4-Series?

Here’s a quick look at used car pricing for the base BMW 4-Series on Edmunds at the time of writing.