9th Aug 2021, 22:16

I think the big thing to watch out for with the BMW turbodiesels is the chain, big time. Unlike this N46 (and previous N42) whose chains are in front (so, easy to check and replace), the diesels have them at the back which makes them difficult to inspect. I would think replacing the chain would be an engine-out job. They appear to be otherwise fairly reliable and are superb performers.

10th Aug 2021, 12:16

Thanks for the advice, I will check all of that.

29th Apr 2022, 09:24

Update: 99,000 km. Three years of ownership. The car was serviced (and the automatic gearbox, separately) just before the mechanical warranty expired. I didn't know the 5-speed automatic was made by GM (I assume in Strasbourg, France); the earlier ones were ZF. Nothing wrong with the gearbox, the mechanic said the fluid was in pretty good shape. I see why it's "sealed for life" - the filter is large and fitted to the sump itself, and it needed around 7L of long-life fluid.

The rest of the car was fine, brake fluid flushed, nothing much else. They noted that the radiator has started to discolour, so has a coolant hose. Sump and vacuum pump gaskets replaced (claimed under warranty) though leaks were minor.

Regarding the oil consumption, over the last 8 months, I have been observing it, the car uses around 1L per 1,500-2,000 km, down from 7-9,000 km for the first two years. The mechanic can't put a warranty claim as they need to show evidence in form of a video of the car smoking. Well, the car isn't showing ANY of the usual signs of worn valve seals: it doesn't smoke (even sudden hard acceleration), idle is not erratic, fuel consumption is consistent, the engine runs fine. There are no puddles of oil, and the gaskets replaced were not leaking significant amounts (which really should pool in the engine bottom cover). The oil consumption is well within the factory guidelines, but if I was previously getting 7-9K km before topping up, it's still a mystery I'd like to get to the bottom of. Else, will deal with the valve seals once it starts smoking.

Anything gone wrong? If I forgot to mention last time, just over a year ago the least used power window cable snapped - rear passenger side. I was surprised that the Valeo part for it only cost NZ$75, then add an hour's labour. Happy with that.

The windscreen washer motor was replaced - NZ$62 for the part plus an hour's labour. It's got an enormous tank - sitting behind the right hand fender, even bends up and around the wheel arch.

The other part that needed replacing was the oil level sensor - it was reading "INACTIVE". The mechanics tested and found that when the oil was still fairly cold, it read the level fine, but acted up when the oil warmed up. Sensor replaced, no more issue. I still think dumping the dipstick was a bad idea, though many car makers are doing it now.

Expected work needed? The rear rubber stoppers in the suspension, cracked but not critical, will deal with that if I fail the Warrant of Fitness inspection. Within the next two years, I expect the radiator to leak (in which case I will do the coolant hose and expansion tank at the same time). Tyres too - the Bridgestone Potenza run-flat tyres are still at around 3.5mm tread, so will likely need replacing within a year. I'm still surprised at how long these lasted given the coarse chip pavement in NZ.

Three years, and I'm still pretty happy with the car. I've read all sorts of bad things about the 4-cylinder N46 engine, and while I won't dismiss those concerns, the car has been good to me. Practically everything has been a wear and tear issue, and the car is now 13 years old. I'm realistic about possible upcoming issues, but hopefully the car is able to last as long as my last BMW which I kept for 9 years. I still miss that car.

4th Jun 2023, 01:14

Original poster here. Update, 113K km. Over the last year, service done last January. Needed a brake light bulb. Just passed the Warrant of Fitness (WOF) yearly test last May, didn't get failed yet on those rubber bump stops, whew - so it gives me time to get them done for the next service. Will do that together with the rear brake pads (wearing out), as well as new spark plugs (last done at 60K km, and from what I have found out, bad plugs are the main cause of coil failure - and, knock on wood, I have not had a coil issue on this car since I got it at 50K km).

Fitted new tyres - Bridgestone Turanza run-flats, fortunately my car has a common size, I think 205/55-16, and not the staggered and wider sizing of those with the M-Sport kits, whose tyres are much dearer. I expect to get 50-60K km out of these.

Oil consumption: It's still hovering around the 1L/1,000 km mark, but has not gotten any worse. And the car STILL won't blow smoke! I'm starting to find this all very amusing, a car whose oil consumption has gotten this bad, yet shows no signs of a worn valve guide seal. Idle is still stable and at the right revs, no smoking, fuel consumption is still the same, performance is not affected. It's been like this for the past two years, with daily car use.

I didn't think I would love this car like my previous 316ti Compact manual, but despite some more brittle internal plastics, the car has been more dependable and reliable than the last car. I can't really complain - I've had it over 4 years and 60K km, and it's now 14 years old.

It'll start needing some work - as I said I expect the radiator to leak (being an automatic with the trans cooler adding more stress to the plastic-capped radiator), the Varta battery is nearing 4 years old so may give up in 1-2 years. Might need one or two HID headlamp bulbs (still the originals). So far, so good.

What would I replace this car with, if I had to, when time comes? Hard to tell. I definitely like the driving position, the perfect lumbar support, the balanced feel of the pedals and steering. Maybe another BMW. But the newer ones are all turbos, and getting a handle of what goes wrong with those engines, and which are the more reliable versions, is still mind-boggling.