[hottuna]

Hi everyone, I have an x3 3.0l Diesel

While returning from holidays towing my 1.2ton (roughly 2500lbs) boat, about 10kms from home my car developed a loud whistling sound when it hit boost. All was fine before then.

There is no engine warning lights on and no overheating.

Its fine without a load, going down a hill or just taking it easy without the boat on the back, however as soon as you put your foot down a little the whistle appears and gets more intense the more you load the engine up

There is NO noise on idle or when you rev it in neutral. And there is NO exaust noise or visible smoke. Its not your typical police siren noise of a bad turbo, its more like a loss of pressurised air noise only while driving. If nothing else the loud whistling sound turns alot of heads


To me it seems a loose intercooler hose or maybe a cracked hose somewhere before the turbo, all the bmw clamps are like a circlip which cant be tightened. Ive taken the engine cover and under car splash trays off for any visible signs, but its so tight in there that i cant see or feel alot.

I purchased extended warrenty with the vehicle, however the earliest i can get it in for a checkup is 2 weeks.

Should i continue driving it?


What could the cause of this noise be?

[RichardBR]

Originally Posted by hottuna

Hi everyone, I have an x3 3.0l Diesel

While returning from holidays towing my 1.2ton (roughly 2500lbs) boat, about 10kms from home my car developed a loud whistling sound when it hit boost. All was fine before then.

There is no engine warning lights on and no overheating.

Its fine without a load, going down a hill or just taking it easy without the boat on the back, however as soon as you put your foot down a little the whistle appears and gets more intense the more you load the engine up

There is NO noise on idle or when you rev it in neutral. And there is NO exaust noise or visible smoke. Its not your typical police siren noise of a bad turbo, its more like a loss of pressurised air noise only while driving. If nothing else the loud whistling sound turns alot of heads


To me it seems a loose intercooler hose or maybe a cracked hose somewhere before the turbo, all the bmw clamps are like a circlip which cant be tightened. Ive taken the engine cover and under car splash trays off for any visible signs, but its so tight in there that i cant see or feel alot.

I purchased extended warrenty with the vehicle, however the earliest i can get it in for a checkup is 2 weeks.

Should i continue driving it?


What could the cause of this noise be?

I have experienced this a few times. All the times it resulted in a turbo breakdown. It could go months from the whisle appeared until it broke down. 4 times...

It's one of the fans in the turbo going nuts when stressed ( throttle ). Causes the turbo to jam, and the engine gets filled with coal bits from compressed smoke particles.

There seems to be a known issue called "3FF0" on these BMW diesel engines. Ask them to check for this...

It doesn't mean that you will experience this, but it feels similar to my problems

Good luck with it