Hi All,
I have been monitoring this site as I have just purchased my second Z4, a 2.5 sport auto in black, my first was a 2.0 se, which although a great car, lacked a little bit of "grunt" imho. I have been particularly interested in the problems relating to the engine management light coming on. This was an issue with the SE. It was a low mileage car on an 07 plate and this problem arose at about 28k. I had been using supermarket fuel, however when my garage looked at it the problem was diagnosed as a build up of carbon in the cat and affecting the lambda sensor. The carbon was burnt off and had no problems afterwards. It has a 30mile round trip to work, mainly motorway, so kept it spinning at around the 3k rev mark as advised and no further probs. However, I always used BP fuel in it. The "new to me Z is already back at the dealers with the management light on, it will be a sensor problem that is for sure as it had been running really well, I think you have to use premium fuel in these cars as they do like a more refined drink, and also rev them quite highly to burn off any excess carbon in the cat. I am looking forward to getting the 2.5 back in a couple of days as I am a huge fan of these cars
I have been monitoring this site as I have just purchased my second Z4, a 2.5 sport auto in black, my first was a 2.0 se, which although a great car, lacked a little bit of "grunt" imho. I have been particularly interested in the problems relating to the engine management light coming on. This was an issue with the SE. It was a low mileage car on an 07 plate and this problem arose at about 28k. I had been using supermarket fuel, however when my garage looked at it the problem was diagnosed as a build up of carbon in the cat and affecting the lambda sensor. The carbon was burnt off and had no problems afterwards. It has a 30mile round trip to work, mainly motorway, so kept it spinning at around the 3k rev mark as advised and no further probs. However, I always used BP fuel in it. The "new to me Z is already back at the dealers with the management light on, it will be a sensor problem that is for sure as it had been running really well, I think you have to use premium fuel in these cars as they do like a more refined drink, and also rev them quite highly to burn off any excess carbon in the cat. I am looking forward to getting the 2.5 back in a couple of days as I am a huge fan of these cars
