The BMW B58 is a relatively young engine. That means we don’t know the full extent of its longevity, durability, or consistency.
Vehicles with the BMW B58 engine have a turbocharged straight-six. It’s part of the new modular family, with each one using a displacement of 500cc per cylinder.
Although some issues can develop, the B58 has done an excellent job of setting the standard high for performance. Since 2016, it has been named one of Ward’s Ten Best Engines for four out of five model years.
Compared to the N55, the BMW B58 offers a 20% improvement in boost pressure. It comes with a closed-deck block design, an improved 11:1 compression ratio, and a 19cc increase in displacement while only adding 18 pounds.
The 5 Most Common BMW B58 Engine Problems
The BMW B58 entered production in 2015. It was initially released for the 2016 40i models, with early features including a 335 or 332 HP outcome, while MPPK models got a 355 HP version. Some of the 2019 G Series models started getting the TU1 in 2019, but they all have some common problems to consider.
Two versions of the BMW B58 engine exist. There is the original namesake and the B58TU1. The latter is also out there as a middle (ML) or high (OL) output option. If you have a later version of the B58TU1OL, you can get an impressive 382 HP.
When comparing the BMW B58TU1 engine to the original, six specific technical changes stand out in the design.
- It comes with an updated cylinder head with an integrated manifold.
- BMW redesigned the crankcase with updated walls and a crankshaft.
- A timing chain redesign comes with the update.
- The automaker revised the fuel system.
- Particulate filters got added to the infrastructure for greater consistency.
- The B58TU1 has split cooling.
After that many changes, there is always an implied risk that some problems can develop. Although the updated engine isn’t that old as of yet, time will tell if there are concerns that require proactive thought.
Until then, the current guidelines follow the most common B58 engine problems we already know about from the automaker.
1. Coolant Loss
It is not unusual for B58 owners to experience below-average coolant levels in their tank. Although it might feel like an overblown issue today, this outcome requires more attention as the technology ages.
Some drivers have even reported that their BMW has low coolant levels in their secondary tank.
Almost all vehicles have a primary coolant tank similar to what the BMW B58 uses to maintain engine performance. The secondary one is an air-to-water intercooler that reinforces the attributes needed to prevent overheating.
There isn’t a specific cause currently known that triggers the excessive use of coolant in the B58. Although some owners have experienced turbo issues, water pump failures, and gasket leaks, most have seen this problem without any known issues or visible fluid losses.
If you’re concerned about losing coolant with the BMW B58 or its updated design, you’ll want to watch for the following symptoms.
- Unexplained Overheating
- Oil Mixing with the Coolant
- Pressure Test System Problems
- Tank Cap Security
- Visible Fluid Leaks
Natural coolant loss is another option for the B58. Since the system is airtight and pressurized, you shouldn’t experience any evaporation. Since the cap is designed to vent pressure, there is the possibility that some might escape if the internal pressurization gets too high.
◼️ How to Fix the Issue of Coolant Loss in the BMW B58 Engine
The easiest way to stop coolant loss is to find where the leak or evaporation occurs. That usually means the cap is loose or over-pressurization occurs.
If there isn’t an apparent leak or loss point, the best solution is to top off the system periodically. You could try replacing the cap. If it is a frequent problem, an experienced mechanic should pressure-test the system for you to determine what is happening.
2. Valve Cover Gasket Failure
Modern turbo BMW engines use a rubber valve cover gasket. It’s a throwback component to the N54 and N55 designs, both of which were known to produce oil leaks.
That means you’ll need to be prepared for the B58 to deliver a leak from the valve cover gasket. In most BMWs, they typically develop between 70,000 to 100,000 miles, but it is possible for problems to develop sooner.
You can also see issues with the plastic valve covers cracking with the B58 engine design. It doesn’t happen as often as the valve cover gasket, but it is a potential issue to review.
The engine does have one advantage over the previous designs that could limit potential problems. Older BMWs went through constant heating and cooling cycles that caused excessive wear and tear on the natural components.
Since the B58 uses a heat encapsulation system, there isn’t as much temperature variation within the engine compartment. This technology traps heat for up to 36 hours, which means the components aren’t exposed to severe changes as part of the driving experience.
We know that the B58 does experience issues at a specific odometer reading range, but it is unclear if the updated version will have the same problem.
◼️ How to Fix a Valve Cover Gasket Failure on a BMW B58 Engine
If you experience a burning oil smell, smoke from the valve cover area, or oil on your spark plugs, the issue might be due to a valve cover gasket failure.
This problem can also cause the low engine oil light to turn on.
You shouldn’t notice any drivability issues when a leak occurs. Minor ones don’t even leak enough for symptoms to display.
The only way to fix the failure is to replace the gasket. If oil leaked onto other parts, it would also need cleaning.
3. Oil Filter Disintegration
Almost every BMW engine deals with this problem at some point. When you look at the B58 design, the oil filter is prone to shearing. The bottom portion tears away, leaving a bit of the product stuck to the housing.
When this happens while the vehicle is under warranty, some dealerships have been down to replace the entire oil filter housing.
If you’re doing the work at home or are out of warranty, you can typically use pliers to pull out the pieces. Anything that can grab the stuck components helps you finish the job before installing the new product.
◼️ How to Fix an Oil Filter Failure on a BMW B58 Engine
Most BMW owners won’t have a significant issue when they experience an oil filter disintegration problem with their vehicle.
Since the oil filter should get switched out with every oil change, you’ll be working with the housing regularly. It is a straightforward process to remove the broken components, inspect the area, and clean away any debris.
If the filter is stuck and won’t move, you’re looking at a housing replacement to finish the job. That’s when a warranty repair might be necessary.
Once the filter disintegrates, you might consider having another oil change happen within 1,000 miles to ensure all debris is removed from the system.
The N54 and N55 engines had a common problem with oil leaks coming from the filter housing. At this time, the B58 engine doesn’t seem to share that issue, but there isn’t enough data to say that the concerns are fixed for good.
4. VANOS Solenoid Failure
BMW uses a specific variable valve timing process called VANOS. This system came out for the first time in 1992, and it has been a common maintenance and repair problem since the beginning.
The trouble is typically confined to the VANOS solenoids when you look at the B58 and other modern BMW engines. They’re relatively inexpensive to replace, but some concerns with this repair must be addressed.
BMW moved the timing chain on the B58 to the rear of the engine, which is where the VANOS components reside. Although you don’t need to lift it to access the parts, you’ll need tools that can reach the area. It’s a much bigger headache than it would be if the front mount were still part of the design.
The solenoids continue to be an issue, and they likely will continue to be one for the B58TU1 update. That’s why this maintenance item should always be in the back of your mind.
When you experience a VANOS solenoid failure with your B58 engine, you’ll notice power loss. The engine starts hesitating, with the bogging especially noticeable at lower RPMs.
The engine has a rough idle with this common problem, and you’ll have a decrease in fuel efficiency.
◼️ How to Fix a VANOS Solenoid Failure on a BMW B58 Engine
When you have a B58 engine in your BMW, it uses two solenoids for the VANOS system. Since they’re located at the back, it isn’t always easy to get in there to replace them.
Unless you feel like investing in specialty tools for this job, it’s usually easier and faster to take the vehicle to an authorized mechanic or your dealership.
Most of the B58 solenoid issues start showing up once the engine hits 80,000 miles. If you’ve made it to the 100,000-mile mark, you’ll want to keep a closer eye on the system.
Some of the N54s can top 150,000 miles without issues in this area, so it just depends on how you drive, and the craftsmanship involved.
5. Engine Won’t Start
The BMW B58 engine has the same common problem as most others in all makes and models of vehicles on the road today. There are times when it just doesn’t want to start.
This issue can happen almost anywhere. It could be after an overnight in your driveway, while parked at a rest area, or in the parking lot at the grocery store.
When your B58 engine doesn’t start, you have three common issues to review to fix the problem.
- 38% of the time, the B58 won’t start because there is a battery problem.
- 27% of the issues in this category are related to the alternator.
- Another 20% of the time, the starter needs to get fixed to resolve the problems.
Your battery is considered dead when it doesn’t contain enough of a charge to start the engine. In most circumstances, that means you won’t have the electrical components in your BMW turn on to work.
The first sign of a dying battery is dim lighting in the cabin when you try to start the vehicle. It might crank slowly for you, but it might not turn over at all.
If there is any charge left in the battery, you will hear a clicking sound. When this problem happens while you’re on the road, the engine might stall, or the warning light might come on. Most batteries need to be replaced every 3-5 years.
◼️ How to Fix Other Starting Problems with a BMW B58 Engine
If your BMW has a strong battery, the next issue to consider fixing is the starter solenoid. It receives battery power constantly, allowing the energy to move to the motor. This action causes the flywheel to turn, forcing the crankshaft to move until the B58 begins operations.
Starter motor failure can happen at any time. When you turn the key, you’ll hear clicking sounds coming from the starter solenoid.
Unlike the issue with the battery, there will be no effort from the B58 to turn over if the starter requires a replacement.
Some drivers might hear a fast spinning sound or a whirring noise.
If your BMW is an automatic, it won’t start if there is a problem in this area. You can “pop the clutch” with a manual if you can get the car moving to about 10 miles per hour, but it could damage the engine if not performed correctly.
Most starters operate consistently for the first 75,000 miles. Once you reach the 125,000-mile plateau, you’ll want to consider replacing the part even if it is still functioning.
The other issue is the alternator to consider. It isn’t always a straightforward diagnostic process when this part fails on your vehicle.
The symptoms sometimes mimic other problems that can develop with the B58 engine. That’s why it might be necessary to work with an experienced shop that can perform a differential diagnosis.
Your BMW comes with an onboard computer and several sensors that can detect the issue of a failing alternator. You’ll notice the light come on your dash when the warning triggers, which means you’ll want to get the vehicle diagnosed immediately.
An alternator that doesn’t perform as it should is known to cause stalling, make odd sounds, or fail to start. You’ll notice electrical issues when it fails.
If you’re driving, your best course of action is to turn off all electronics since the battery won’t charge, including your headlights. Then go safely to the nearest repair shop.
It would be safer to pull over and have the vehicle towed, if possible.
Best Tool Set for Working on Your BMW
If you’re like me, you want to take care of the repair work at home. It’s not that I don’t trust people with my car, but I prefer to know what parts are going in there and the quality of the craftsmanship involved.
That doesn’t mean I try to fix everything. There are times when a repair is over my head, even with the benefit of YouTube videos and technical guides. That’s when I take a trip down to my dealership.
For everything else, I like to use the DeWalt DCK1020D2 20V combo kit. You’ll get all the portable tools you need for around the house or working on vehicles with an 84-piece mechanics toolset.
I love the compact drill driver in this combo kit. It delivers 300 unit watts, which is enough power for almost anything I encounter in the garage or around my property. I’m also a big fan of the keyless blade clamp on the reciprocating saw for those odd jobs that come up every so often.
As for the mechanic’s set, it uses a 72-tooth ratchet. That means you only need to swing the tool five degrees to get bolt or nut movement, which is perfect for the tight spaces around the B58 engine. The design includes a quick-release button for changing sockets, allowing you to move between jobs quickly.
The mechanic’s set comes with full-polish chrome for extra corrosion resistance.
If you want to create a shop at home, the DeWalt DCK1020D2 20V combo kit is an investment that makes sense. You can work on your BMW B58 engine, take care of the to-do list each weekend, and handle each job with finesse.
No one ever wants to have their vehicle have a breakdown. When something does happen, being prepared for it is the next best solution. After an investment into emergency roadside services, I highly recommend having tools you can trust at home.
