You are probably here to gauge how much money you’d need to spend on the sweet-looking 3 series that you have spotted at your local used car dealership. Yes, you are at the right place, my friend.

I have bought used cars and articles like this one have helped me get a better deal or just save myself from a money pit.

Talking about money pit, the BMW F30 3 series, just like any other BMW car has its share of common problems. Now, the good news is that these are more like maintenance items for a BMW. And more or less, every BMW owner repairs/replaces these things throughout their ownership.

So, let’s look at what are the common problems of the BMW F30 3 series and their solution. These are in descending order of their severity.

Timing chain failure in inline-four engines

BMW N20/N47 timing chain
Timing chain failures have been present in BMWs for quite some time now. The brand employed the timing chain to avoid any belt maintenance. It would have saved money, of course. But, unfortunately, it did not turn out the way they thought it would.

Timing chain guides fail and make the chain lose. The first sign of this failure is a rattling noise at a cold start. At this point, no damage has been caused.

As the owner ignores the noise, the timing chain might jump a tooth and mess up the engine timing. This results in poor engine running and the same can be observed with smoke, startup struggle and vibrations.

This is your cue to change the timing chain kit.

And if you decide to let the car run this way, then God help you. You are now just asking for the chain to break letting the valves and piston and rods fuse and become one!

There are pieces of evidence that changing engine oil at about every 5000 miles has helped prevent these issues altogether. But then some people say otherwise. Your best bet is to change the engine oil regularly and if your stars are not in your favor that timing chain rattle does come, just change that darn thing.

Water pump and thermostat

BMW thermostat housing
The water pump on the BMWs are electric and are made out of plastic housing. As a lot of people don’t change the coolant as a maintenance item, the coolant turns acidic over time. And with that, it is easier for the pump housing to break leading coolant leakage and a failure of the pump altogether.

A failed water pump can cause severe engine damage if not diagnosed on time. And rebuilding an engine costs much more than replacing a water pump.

It should be replaced at about the 60-80k mile mark. And since you are there, replace the drive belt, tensioner and thermostat as well.

Dual mass flywheel

The dual mass flywheel on manual transmission BMW F30s was problematic and needed an early replacement.

These flywheels have a spring-loaded shock absorption mechanism built into them and so they act as vibration dampeners. The result is smooth shifting and transition of gears.

When the dual mass flywheel goes out, the car would experience rattling noise in startup and harder shifts.

The solution is to replace the dual mass flywheel. Also, check the clutch condition when you are there.

Faulty injectors

Injectors are some of the ‘for life’ parts but often I have seen that they need replacement. The main reason is feeding cheap quality fuel to the car. You must always choose the best fuel bunk in your city so that there is no fuel doping.

The dirt can easily clog the injectors over time. If you have been experiencing cold start problems, low fuel efficiency, misfires and overall worse engine performance, it might be possible that the car’s injectors are failing.

Oftentimes, a clogged injector is accompanied by a failing fuel pump as well. The reason is the same, dirt in the fuel.

So, the best way to avoid this situation altogether is to stick to best quality fuel.

If you already have a clogged injector, you will need to rebuild or buy new injectors. Since it is a German vehicle, injectors do cost a lot. So, find a reputed aftermarket one like Bosch. It is good quality and you save some money as there is no BMW tag on the part.

Spark plugs and ignition coil

Spark plugs are more of a maintenance item. And you can expect them to go out at about 60-90k miles. By default, the car comes with iridium spark plugs and they last for more than the normal ones (copper).

At about the same mileage, BMW gasoline engines may experience misfires and you might discover that one or more of the ignition coils have gone bust.

The best way to check whether the problem is caused indeed by the ignition coil is to get a scan tool and read codes. Suppose, the code is related to cylinder one misfire, just swap its coil with cylinder three and wait for the code to pop again. If the code has shifted to cylinder three, then you know for sure that it is the ignition coil.

The solution is to change the faulty ignition coil with a new one. FCP Euro is a great place to buy OEM parts for a discounted price. Or Amazon also has NGK coils for BMW engines.

Steering knock

A worn-out steering rack can cause a steering knock noise. In the earlier stages, the repair would require you to replace the steering rack which would cost about USD 3700. But, now that it is a known issue, BMW produced a repair kit to get rid of this problem.

The repair kit includes grease, bush, spring and some clamps. On the steering rack, there is a bushing that wears out and the steering would produce knocking noise. You need to get under the car and replace the bush with the supplied one. This should take an hour or so and about USD 50.

Sticky door handles and broken AC vents

Nothing unusual. The sticky handles can be replaced or better, have an upholstery guy redo them. It is cheaper that way. The broken AC vents have cheaper alternatives than what BMW sells you.

And that is about it. I hope it enables you to take better decision when buying a used BMW F30 3 series.