Faults:

Temperature sender: Replaced by myself.

Coolant reservoir holed: Replaced FOC by dealer.

Blocked CCV: Cleared by dealer.

Audio speakers/Logic7: Partially resolved FOC by dealer.

Ebox fan faulty: Replaced by myself.

General Comments:

I've always loved these pre-facelift E66s. As well as the faults above, I had the transmission serviced including the all important bridge + other seals, changed the CCV filters and pipework and IVM.

I thrashed this car hard for the 10k miles I put on it and it stayed reliable. Longer drives were approx 22 MPG, dropping to 14 MPG in town.

I only sold it to help finance a house move, but I don't think I wouldn't have another one; as for all the talk about it being the sportiest of the limos, it wasn't happy getting caned down the back roads. It did it, it just wasn't happy, and OTOH motorway driving wasn't as 'limo' as you'd hope.

I used to bemoan its lack of torque, but looking back it was plenty, it's just the engine and transmission was SO smooth!

For all the doom laden talk about these cars, I thought it's best to show they're not all endlessly unreliable.

Faults:

I'm indicating repairs as "common" as there are many other individuals on BMW forums that discuss a lot of these issues.

- Valve stem seals (common, costly repair).

- Coolant leak (common, costly repair).

- Logic 7 amplifier malfunction (causing crackling in rear speakers - common).

- Brake booster and vacuum pump malfunction (recall).

- Driver's side restraint malfunction light warning (common. There is a recall for the passenger side for some years, but not the driver's side).

- Parking brake malfunction (plastic gears in the motor break after some time - common).

- Oil leaks (cracked oil pan from wear of oil changes - the bolt used as the oil plug may eventually cause the oil pan to crack).

- Other miscellaneous oil leaks.

- Control arm bushings worn (normal wear and tear, mine was accelerated by oil leaks).

- Possible guibo (flex joint) malfunction (common).

- Oil pressure sensor malfunction.

General Comments:

Great car to own if you can afford the repairs. You will have to repair the majority of the problems I mentioned above if you are buying it used.

The car runs very well, powerful acceleration and smooth ride. I have never been left stranded anywhere because the car just won't start or due to a message on the computer display (i-Drive) indicating that I should stop driving, which is a plus.

I found the i-Drive system relatively easy to learn. Most of the younger generation shouldn't have much of a problem figuring it out. It can be a little time consuming entering addresses for the navigation, mainly because I am used to using my phone that has a keyboard to type in addresses. The navigation does however assist in bringing up street names as you type.

I enjoy this car, which is probably why I keep repairing it. I like the look and feel of it, and being a taller guy (6'3"), it is very comfortable for me. If you can do basic maintenance yourself, that would save you some money as oil changes, brake and rotor jobs etc can be pricey on German cars.

All this being said, I do not think I would purchase another German car (or at least not an older BMW) due to the running cost, although I enjoy this car.