2004 VW Touran TDi - Humming Noise coming from Engine - JulesD

I recently had my 2004 VW Touran Tdi car serviced, break pads replaced etc. Nothing major. But when I got the car back I started hearing a humming noise from the engine, which felt like I was in the wrong gear. The car went back in to have a new cam belt put in, and the mechanic explained alternator should be replaced soon too. When i drove the car home, the engine was making another new noise, like something was hitting a fan (the noise would change depending on speed). Then it lost all power when it came to a standstill at traffic lights. Some how I got it going and returned to garage - at one traffic light on hill, i though I was never going to make it. Turning it on/off helped. Once car got going, it drove normally.

The garage also mentioned to me before that perhaps the humming sound is related to the Turbo and has warned me that this could be an expensive repair.

Car is now back in the garage and I am yet to hear what they think it is....\

Until now, my car has been very reliable....need to top up coolant occassionally.

Any ideas what might be wrong? Obviously now my car is at local garage I can't get the turbo checked at VW dealer.

2004 VW Touran TDi - Humming Noise coming from Engine - Peter.N.
Turbo's usually make a whistling noise, never heard one hum, if the cam belt is over tight it can cause a whine, it could just be something vibrating. Without hearing it very difficult to say.
2004 VW Touran TDi - Humming Noise coming from Engine - craigy1980

sounds like wrong oil or too low an oil level. ive worked for vag or 12 years or so and know the correct oil is crucial . should be 5w-40 or 5w-30 full sythetic oil. turbo could have seized due to lack of oil explaininlg noise and ack of power. maybe the cambelt has been done wrong or a tensioner has moved or failed.

2004 VW Touran TDi - Humming Noise coming from Engine - Roly93

sounds like wrong oil or too low an oil level. ive worked for vag or 12 years or so and know the correct oil is crucial . should be 5w-40 or 5w-30 full sythetic oil. turbo could have seized due to lack of oil explaininlg noise and ack of power. maybe the cambelt has been done wrong or a tensioner has moved or failed.

Yes the correct oil (ie VaG 506 0r 507 as opposed to just synthetic) is crucial on these engines to prevent cam wear due to the cam driven unit-injectors, but a short period without the correct oil would be unlikely to cause a humming noise.
2004 VW Touran TDi - Humming Noise coming from Engine - Roly93

A low humming noise is usually the sign of an over tight cam belt, this definately needs immediate attention. Less likely to be the alternator as this would be more of a growling noise.