Auto Express's running costs ratings are based on our Driver Power survey of over 30,000 car owners. Ratings are the average for all owners of this car who responded. Individual owners’ ratings and comments appear below.
09-reg Petrol, Owner for Less than a year

Some of the interior materials are a little cheap and plasticky, but I really like the style and design, both inside and out.
The rain channels on the roof do not work very well, annoyingly, water from the roof runs into the car if you have the window open (or sometimes in the wet when you go to open the door as the window drops half an inch and water on the guttering drops into the car). I have had a problem in the frost when the windows froze shut and I could not get the door open - I put some grease around the window edge to cure the problem.
The rear ride quality is quite jiggly, like the tyres are over-inflated, I did not notice that on the 35i I test drove (mine is the 30i and has different size tyres).
The Parking sensors are a little slow to react. I found this out when I bumped into a wall - the first thing to make contact was the nose at the top of the grills, that is now subsequently pitted ! I suppose you may argue that that is part of the bumper !
The engine (oil) seems to take a long time to warm up.
Other than those minor niggles and the fact that the product + extras is quite expensive, it is an excellent car and overall I am very pleased with it.

Cost: 3/5
05-reg Petrol, Owner for 1 to 3 years

Really good fun to drive, alot of cobbled streets around here that turn it into a boneshaker but it still keeps going. Visiting the in laws is now a joy as they live in the middle of the nowhere with miles of deserted country roads needing to be navigated to reach them, a bit of sunshine, top down and the only downside of the journey is that I can't hear the wife very well..... in short love it and will definately replace with the new model next year. Now if only they would do a similar scheme for the wife.

Cost: 2/5
2003-reg Petrol, Owner for less than a year

Superb car, but due to high mileage I'm having the occasional small component fail (bearings etc). For a "sports car" with over 200 bhp and a bmw badge the z4 is surprisingly cheap to run in most senses, even servicing is no different to that of a 3 series.

Cost: 4/5
2006-reg Petrol, Owner for 3 to 5 years

Only let down by flat battery - I replaced it with bosch s5. For a 155 mph sports car it seems relatively inexpensive to run (touch wood!). Happy to tootle at 30 in 6th and will respond to the throttle seamlessly.

Cost: 5/5
55-reg Petrol, Owner for 1 to 3 years

Great car, driven it over to eastern europe a couple of times with all our snowboard gear in the boot!!. Would recomend it to anyone who is willing to give it a chance.

Cost: 5/5
2003-reg Petrol, Owner for 1 to 3 years

Only issue was the front wiper linkage breaking. Fuel economy is good for the type of car.tax is a little high but not in the top bracket.bmw parts are expensive.

Cost: 3/5
2006-reg Petrol, Owner for more than 5 years

No breakdowns, but emission sensors have failed twice, and centre stop light in boot has fallen out twice. Bmw dealers are very expensive!

Cost: 3/5
2006-reg Petrol, Owner for 1 to 3 years

Stuck bonnet catch, both window motors needed replacing, intermittent electric fault with alarm. Expensive (due to sports car).

Cost: 2/5
2003-reg Petrol, Owner for 3 to 5 years

100% reliable so far. Servicing through a non-franchised specialist is still expensive, parts expensive but rarely required.

Cost: 3/5
2006-reg Petrol, Owner for 3 to 5 years

No failures to note. 3.0 sports car = 25 - 30mpg with roof droppedno service costs for 3 yearsinsurance 260 per year.

Cost: 4/5
08-reg Petrol, Owner for 1 to 3 years

I love my car - I used to think bmw drivers were very arrogant and inconsiderate. I suspect I am now !

Cost: 2/5
2007-reg Petrol, Owner for less than a year

No problems so far. Decent mpg for this type of car but expensive parts etc due to the bmw tag.

Cost: 3/5
59-reg Petrol, Owner for Less than a year

Love it,even though I haven't had it for long,it's my 5 BMW and I think they are great!

Cost: 3/5
2007-reg Petrol, Owner for less than a year

No issues to date. Tyres are expensive (ł250 each)but everything else is as expected.

Cost: 4/5
59-reg Petrol, Owner for Less than a year

A brilliant car I've awaited for four years. All I expected and wished for.

Cost: 3/5
2003-reg Petrol, Owner for 1 to 3 years

Lambda light - leaky hosepipeoil pressure light lights up. no reason why

Cost: 3/5
09-reg Petrol, Owner for Less than a year

A "proper" sports car, challenging to drive, rewarding and thrilling.

Cost: 5/5
04-reg Petrol, Owner for 1 to 3 years

This is my second Z4. It is a pleasure to drive and own ,I love it.

Cost: 5/5
2006-reg Petrol, Owner for less than a year

No issues. Far better fuel economy than my previous car.

Cost: 4/5
2006-reg Petrol, Owner for 1 to 3 years

No issues. Servicing v expensive.

Cost: 2/5
2010-reg Petrol, Owner for 1 to 3 years

It does what it says on the tin

Cost: 5/5
05-reg Petrol, Owner for Less than a year

The ultimate driving experience

Cost: 3/5
59-reg Petrol, Owner for Less than a year

sporty and stylish

Cost: 3/5
54-reg Petrol, Owner for 1 to 3 years

Best ever

Cost: 5/5