Firstly my car is a 2009 A4 SE saloon 2.0 TFSI. It has the new 2.0 litre engine which is the 211 PS version. The oil filter is on the top of the engine at the front (see later)
On start up in the mornings or after the car has stood for a long period - eg. all day, I get a loudish "urzzz-sqeal" sound for about 2 seconds. It doesn't happen when the car is warm.
In case things were not as they should be I took the car back and left it with the Dealer for them to listen to over 2+ days. The technician(s) had no problem in hearing and acknowledging the noise.
The first thought was it was the starter motor not disengaging correctly. Rust on the pinion was mentioned !!!??? Next the fuel pump charging was mentioned but was discounted when I pointed out that this could be heard as normal when only the ignition was switched on - but the unknown different noise comes at stage two when the car is actually started.
The final diagnosis suggested (so far) is that the sound is made by the oil pump or oil pumping up to the filter which is on the top of the engine. The theory is that the oil drains to the sump when it is left and when the car is cold it has to pump to the top of the engine and filter - hence the noise ??? They said they had started an A5 in the showroom with the same engine and it made the same sound ??? The technician was open about the fact that they are still learning about this new engine. I hope I'm not being "palmed-off" by the stealers particularly as I took the car in a.s.a.p. in case there was a potentially serious problem which could cause further damage - and thereby save them and Audi a big costly repair.
Anyway I've got the car back still making the noise on cold starts. At least the problem, if it is one, is on record. My thoughts on this sort of noise tend to go towards things like dry bearings on fans, pulleys, alternator, tensioner etc. Also if a secondary air injection pump is fitted this only activates on cold starts so this could be a possiblity. I acknowledge that because the noise in so brief it is difficult to trace.
Anyway I wonder what you guys think? Would an oil pump make this pronounced sound? Has anyone with the same engine noticed this sound and if so has it been diagnosed? Any Audi tech. guys out there who know what it is for sure?
I now intend to put my concern to Audi Customer Support via e-mail so that it is on record with them as well as with my local Dealer. I'll also probably post this elsewhere.
Anyway Guys thanks for giving this your consideration.