Brand new

[The G]

Hi all.
I'm completely new to bmw's and have purchased a 2003 bmw 318i se.
I was half ass'd looking for a bigger car and this one literally pulled up in front of me for sale. Now I'm an e46 fanatic although still brand new and learning.
I love my e46 and want to do all I can for it. I know I've come in at a learners level but think it's for the best with my lack of experience.
I have looked into common faults and dealt with problems I've had so far which have been knocking from the rear drivers side, coolant leak, and corroded sensor wires. I Also have a non working diamond key fob, warning light for rear drivers side lights although they all work and I'm having the airbag replaced under bmw recall.
Currently it has 125k on the clock and is running fine. I guess I have a few questions. 1. What should I replace now. 2. What should I keep an eye on. 3. What work could I do myself as a complete beginner. And last of all what upgrades can I do to get the best drive and enjoyment. I want to know it's mechanically sound and running at its best and up to date with styling.

Thanks
G

[MarcoZandrini]

Welcome! The E46 platform is one of my favorites. I owned a 2001 330Ci for 17 years before moving in to my current bimmer, a 2018 M240i.

You’re asking the right questions. Did you get any service records with the car? Service records tell you how well the car has been maintained. And, I assume the car has a manual transmission.

What should be replaced immediately? How many miles/months on the oil and filter? Anything greater than 7k miles means it’s time for an oil and filter change. You’re in the UK, so a fully synthetic 5W30 oil with the “BMW LL01” logo on the bottle is fine. The oil filter needs to be made by Mahle as aftermarket oil filters aren’t up to the task. There have been horror stories about aftermarket oil filters disintegrating in the oil filter housing (OFH).
BMW used to tout “lifetime fluids” for the transmission and differential. Hogwash! The transmission fluid should be changed every 50k miles. Same for the differential. Both require a fully synthetic lubricant. Check with the dealer as far as specific requirements.
The cooling system is the Achilles heel of the E46. BMW used a ton of plastic in the system. Here in the US we say that the cooling system needs a to be overhauled at 100k miles. That includes all hoses, the water pump, thermostat, expansion tank & cap and the radiator if it’s leaking. Installation of aftermarket cooling system parts is strictly verboten! These engines are aluminum and do not tolerate overheating. The coolant needs to be a 50/50 mix of BMW coolant and distilled water.
Factory parts don’t have to come from the dealer. There should be online vendors that sell parts made by the suppliers to BMW. These are called original equipment (OE) parts.
Lastly, check out E46Fanatics. It’s a great website.

[The G]

Welcome! The E46 platform is one of my favorites. I owned a 2001 330Ci for 17 years before moving in to my current bimmer, a 2018 M240i.

YouÂ’re asking the right questions. Did you get any service records with the car? Service records tell you how well the car has been maintained. And, I assume the car has a manual transmission.

What should be replaced immediately? How many miles/months on the oil and filter? Anything greater than 7k miles means it’s time for an oil and filter change. You’re in the UK, so a fully synthetic 5W30 oil with the “BMW LL01” logo on the bottle is fine. The oil filter needs to be made by Mahle as aftermarket oil filters aren’t up to the task. There have been horror stories about aftermarket oil filters disintegrating in the oil filter housing (OFH).
BMW used to tout “lifetime fluids” for the transmission and differential. Hogwash! The transmission fluid should be changed every 50k miles. Same for the differential. Both require a fully synthetic lubricant. Check with the dealer as far as specific requirements.
The cooling system is the Achilles heel of the E46. BMW used a ton of plastic in the system. Here in the US we say that the cooling system needs a to be overhauled at 100k miles. That includes all hoses, the water pump, thermostat, expansion tank & cap and the radiator if itÂ’s leaking. Installation of aftermarket cooling system parts is strictly verboten! These engines are aluminum and do not tolerate overheating. The coolant needs to be a 50/50 mix of BMW coolant and distilled water.
Factory parts donÂ’t have to come from the dealer. There should be online vendors that sell parts made by the suppliers to BMW. These are called original equipment (OE) parts.
Lastly, check out E46Fanatics. ItÂ’s a great website.

Hi Marco.
Thanks for the warm welcome.
Yes im in the sunny UK. Yes manual transmission with some service history. Part dealership part private. Feed back from mechanics who have done any work seems to say it's not been abused yet not looked after quite the way it should be.
Oil and filter has not been changed as far as any records show and I haven't so job No. 1?
Mahle filter it is. and thanks for the oil recommendation, that's something I've looked into more than once with slightly different views.
So, oil, filter, transmission fluid, thermostat, water pump, hoses, expansion tank done, expansion cap, radiator fine so far.
As a newbie this does seem a lot but from what I've read,it Is worth it. And from my experience with a bmw so far, when running fine, it's the best car I've ever driven.

Brilliant help and advice
Thanks
G

[harrier]

Next you have to decide which owner you are. If you are cash strapped, then good news you hit the right stuff first. Make sure you change all the other fluids - differential, gearbox, and brake. Some would also say steering - remember steering is ATF not power steering fluid. I’d also get a Bluetooth OBD device and OBD fusion.

The other owner is a PM (preventative maintenance) owner who wants to get ahead of issues and restore lost driveability. This is a fork in the road. If you are this owner, you want to get as close to the original driving experience and you would rather replacing an aging part than get stranded.

If you are the second, here is my advice:
1. Replace the CCV and service the Vanos and DISA. Replace the fuel filter
2. Replace all the rubber vacuum hoses as well as the caps and hose behind the intake. Replace the upper and lower intake boot.
3. Replace the flex disc, tranny and engine mounts, center support bearing and the steering giubo.
4. Replace pre-cat O2 sensors - they have 100k lifespan
5. Consider replacing the shifter linkage bushings (very satisfying!)
6. Have the suspension thoroughly inspected and consider replacing all bushings and bearings as well as shocks, struts front control arms and mounts
7. Replace the fuel pump (probably should be #3

Learn how to use OBDFusion and look at your long term fuel trims.

You don’t need to do any of this, but for about $3k you can vastly improve reliability and the driving experience.

No need to debate if you are driver 1. Just turn it on, drive it, fix stuff when it breaks and enjoy!