
The BMW 3 series is a popular car that has existed for many generations. Also known as the E46, the 4th generation 3 series contains models like the 323i and 325i. While there is nothing necessarily wrong with the 3 series, all cars have their common faults. This article reviews common BMW 3 series E46 problems, years 1997 to 2006.

Top 5 Problems on the 4th Gen BMW 3 Series E46 (1997 to 2006)
1. Oil Leaks

Symptoms of Oil Leak Problems on the BMW E46
- Oil filter housing leak where the housing attaches to the engine block
- Oil leak below the oil filter housing or oil dripping on the exhaust manifold
Causes of Oil Leaks
The seals on the filter housing can weaken over time and eventually crack.
The valve cover gasket is also a common part that can leak oil. Oil dripping onto the exhaust manifold and possibly a smell of burnt oil are signs of a valve cover gasket leak.
How to Fix Oil Leaks
Replace the valve cover and gasket sometimes or valve cover.
2. Coolant System Leaks
Symptoms of a Coolant System Leak on the BMW E46
- The coolant reservoir that is plastic can crack over time
- There may be a low coolant leak light on on the dash
- May smell a sweet smell like maple syrup
- Puddle of coolant under the vehicle—BMW coolant from the factory is blue
How to Fix Coolant System Leaks
- Check the coolant level with the coolant cold. Remove the cap and an indicator will appear. The key will show where the coolant level will be. Replace the coolant if necessary.
- Replace the coolant reservoir if it’s cracked.
- The thermostat housing and water pump are also common areas that can leak.
3. Crank Case Control Valve

Symptoms of a Bad Crank Case Control Valve
- Check engine light for a lean or a rich condition. The breather valve tube may leak oil
How to Fix the Case Control Valve
The CCV system is located underneath the intake.
The breather valve tube extends down. Repair requires removing parts to access it. One method is to remove the intake. When replacing the valve, we recommend replacing the tube also since they can crack and deteriorate.
4. Front Lower Control Arm Bushings

Symptoms of Bad Control Arm Bushings
- The rubber bushings on the control arms that hold the backside of the control arm may deteriorate
- Noise when going over bumps or turning
- Very bad bushings can pull the steering wheel when braking
How to Fix Bad Control Arm Bushings
The bushings can be pressed out and replaced separately. It is not necessary to replace the whole control arm or a small amount of movement is okay. Significant movement is a sign of bad bushings.
The bushings are not too difficult to replace. The repair requires removing the control arm and pressing the bushings out.
5. Window Problems
Symptoms of Window Problems on the 1997 to 2006 BMW E46
- Window regulator may make a cracking noise or may not work at all
- Window won’t go up or down or may be stuck
How to Fix Window Problems
Can replace the window regulators separately from the motor
Replacing the window regulator requires removing the door panel, tapping up the glass with painters tape, loosening and removing the regulator and reversing the procedure for reinstall.
Fix Your BMW 3 Series E46 Yourself
Fix BMW 3 series E46 models like the 325Ci and the 325Xi with 1A Auto’s how-to videos that have step-by-step instructions for many repairs.
4th Generation 1997 to 2006 BMW 3 Series E46 Models
Related Content
- Why is My Car Leaking Oil?
- Burning Oil Smell? [Diagnose & Fix Valve Cover Gasket Leak]
- How Can I Tell If I Have a Coolant Leak?
- Car Window Rattling?
- How to Diagnose and Fix A Squeaky Car Window
- How to Fix a Car Window That Won’t Roll Up
- Why Is My Power Window Not Working?
Shop BMW 3 Series E46 Parts

