BMW has produced some of the best engines over the years. However, some engines have proven to be more problematic than others. For instance, the BMW N47 engine has several issues that users have complained about over the years.
The most notable problem of the BMW N47 is the timing chain issue. Other problems include EGR problems, failing return springs, faulty crankshaft sprocket, thermostat failure, faulty cooling system, and water pump issues. To avoid most of these issues, ensure proper care and maintenance is observed.
What are the common problems with the BMW N47?
Timing chain issues
This is the main issue with the BMW N47 engine. It also becomes more problematic when your car hits around 60,000 miles. The N47 engine is susceptible to extreme timing chain wear and tear, leading to premature failure. Some of the common signs of a bad or failing timing chain are rattling noise at the rear of the engine and engine light.
A bad or failing timing chain is costly to repair or replace. Depending on the gravity of the problem, you may have to replace the engine or repair the timing chain. Some of the most affected models are BMWs with N47 engines built between March 2007 and January 2009. Timing chain issues are also common in BMW 1, 3, and 5 Series.
Failing return spring
This was a fault by BMW but they never accepted it. The return spring on the turbo’s wastegate was not initially lubricated or even covered. As a result, it led to early failure making the wastegate stay somewhat open. And with successive losses in compression, fuel usage increased by more than 30%.
To fix this problem, you will have to take the car to a mechanic to replace the failing return spring with a new one.
The work of the EGR system is to assist the car to meet the stricter emissions. However, if the EGR becomes faulty, it won’t perform its function well. When the sensor becomes covered in soot, it affects how the EGR works. As a result, it makes more and more exhaust air recirculate into the intake.
In the process, the hot exhaust gases make the plastic intake manifold melt and leak out in some cases. Another EGR problem comes from a damaged vacuum hose. If this hose has a hole, the EGR cooler won’t get bypassed during the engine warmup. In the end, it will cause a build-up that can cause melting holes and leaks or even fire.
Faulty crankshaft sprocket
Like the failing return spring, the crankshaft sprocket is also a manufacturing defect. This is because the sprockets drive the chain to the pressure pump on the camshaft because of an error from the plant during the manufacturing of the N47 engine. As a result, it will cause the chain to snap in half and bring grave harm to the engine.
Faulty cooling system
The cooling system is one of the most vital parts of a car as it circulates water and coolant throughout the engine. This helps the engine to operate at an optimal temperature. However, the cooling system in the BMW N47 becomes faulty and affects the performance of the engine. The main culprits are the water and thermostat.
Some of the signs of a bad cooling system are engine overheats, low gas mileage, white exhaust smoke, external coolant leak, and smoking. Check the coolant and water pump and replace the faulty part immediately.
Power steering pump failure
Another notable issue that can be noticed on BMW N47 engines is a failing power steering pump failure. If a power steering pump is bad or damaged, you will notice oil spillage around the cap of the steering oil reservoir. Replace this part as fast as possible to avoid further issues.
Is the BMW N47 engine reliable?
No, the BMW N47 engine is not reliable. This is because many users have reported several problems over the years. Besides, its problems are very serious and can cost thousands of dollars. For instance, a serious timing chain problem may require changing the entire engine.
What BMW model years are fitted with the N47 engine?
There are many BMW model years that are fitted with the BMW engine. Most of the cars with BMW N47 engines were built between 2007 and 2009. Some of them include BMW 1-Series E81, E82, E87, and E88. In the 5-Series, we have the E60, E61, and M47. While in the 3-Series, we have the E90, E91, E92, E93, and X3.
Is it expensive to maintain a BMW with the N47 engine?
Yes, it is very expensive to maintain a BMW model with the N47 engine. This is because this engine comes with lots of issues. Additionally, these issues are quite costly to deal with and cumbersome to fix. On top of that, BMW parts are very expensive, making the overall cost of maintaining this car to be very costly.
On average, you may have to spend over $1,100 to maintain a BMW with the N47 engine. But if it develops a serious issue, this cost can reach even up to $8,000. For instance, replacing a bad timing chain tensioner can cost you at least $830.
How long do the BMW N47 engines last?
It depends on how well you maintain the car. BMW N47 engine is very unreliable and starts experiencing issues as early as 40,000 miles. Things like timing chains have to be changed after 60,000 miles. Regardless, proper care and maintenance can make the engine last over 250,000 miles.
However, the cost of maintenance is quite high as this car has a lot of issues that you will have to deal with over the years.
If you own a BMW model with the N47 engine, you should always take good care of your car to avoid most of the above issues. Change the timing chain every 60,000 to 100,000 miles. What’s more, clean your vehicle’s EGR sensor on timely oil changes to prevent unnecessary soot build-up.
Overall, you need to keep an eye on the engine parts and adhere to scheduled service maintenance. But if possible, avoid investing in a BMW model with the N47 as it is one of the least reliable BMW engines ever built.