You may have my problem which is a whine when cold which appears to emminate from the engines passenger side and slowly subsides as the car warms up and then 99.9% disappears when upto operating temperature. I've noticed the whine is worse in colder air temperatures and less so on a hot day when the engine is cold. Its definitely not the fuel pump as its coming from the engine bay. Mines done this since new and it went in twice, first visit the dealer changed the waistgate solenoid valve which didn't cure it, second time they said it was normal when compared to another 2.0l which did have a whine but less marked so I'm just living with it. Mine is quite loud at times and really just sounds rubbish until its warmed up, not helped with the exhaust resonance on initial start up and rattling engine which is apparently normaljagi00 wrote:Update on my post above. Both the boss and I agree the sound appears to be coming from the right rear somewhere when listening inside the cabin. Couldn't hear it outside so opened the petrol filler cap and stuck my ear against it - nothing! Same story with the boot opened. I'm now wondering since it seems to be associated with a cold start, if the sound is actually coming from under the bonnet and just cabin acoustics making it appear coming from the right rear quarter. Any thoughts anyone?
I've done a fair bit of searching on the internet regarding N20 engine whine and its mentioned in various road tests attributed to the turbo spooling up however there are also reports with 328i X owners having this problem I'm experiencing to be told by dealers its normal and some X3 owners who have had the problem solved with a new turbo. Personally my take on it is the turbo bearings being out of tolerence when cold.
There is also another known noise either electrical/hum/whine which comes through the air vents when on the throttle and disappears when you take your foot off so it could be this as well, all Z4s seem to suffer this.
Tim.