Whistling noise on acceleration - New Turbo (TDI 170)

[b0redj0rd]

Hey guys, recently the turbo gave up on my 07 TDI 170 and I have had a reconditioned unit fitted this week. I have had the car back for around 24hrs and when I went to collect the garage said they'd heard a whistling type noise coming from the engine, which they thought could be the vacuum hoses.

The garage is going to have the car back on Monday to replace a 'flexi-pipe' in the exhaust, and I'm guessing they'll be looking at the whistle at this time too but I'm wondering if anyone had any ideas what this may be - baring in mind this is a newly reconditioned turbo, the car pulls fine and doesn't kick out any smoke (oodles of smoke before the turbo gave up however!). Just to add, the whistle wasn't present with the older turbo.

The sound is seemingly (to me, baring in mind that I've only really driven the car for 10 miles or so) worse when the engine is cold and increases in pitch as you accelerate and sounds pretty much like a police siren.

Thanks guys,
Jordan

[GVK]

While it shouldn't be up to you to look at, they should be checking if any of the blades on the turbo are bent, get a camera in the intake side of the turbo if you can't see in there.

I once put a new turbo on a Fiat panda 100hp and after a few days it was making the police siren noise, put another turbo on and it did the same, turns out there was a lot of moisture in the pcv system and as it was winter time the turbo was effectivley freezing up and bending the fins on the turbo! Once cleaned out and yet another new turbo it was fine. Good job it was under warranty at the time!

[b0redj0rd]

While it shouldn't be up to you to look at, they should be checking if any of the blades on the turbo are bent, get a camera in the intake side of the turbo if you can't see in there.

I once put a new turbo on a Fiat panda 100hp and after a few days it was making the police siren noise, put another turbo on and it did the same, turns out there was a lot of moisture in the pcv system and as it was winter time the turbo was effectivley freezing up and bending the fins on the turbo! Once cleaned out and yet another new turbo it was fine. Good job it was under warranty at the time!

Thanks very much, that is good advice - I'll ask them to do that.  The reconditioned unit has come with a 2yr warranty, so hopefully they'd replace it if that is the case - obviously the garage would be charging me for the removal and refit unfortunately! 

[GVK]

While it shouldn't be up to you to look at, they should be checking if any of the blades on the turbo are bent, get a camera in the intake side of the turbo if you can't see in there.

I once put a new turbo on a Fiat panda 100hp and after a few days it was making the police siren noise, put another turbo on and it did the same, turns out there was a lot of moisture in the pcv system and as it was winter time the turbo was effectivley freezing up and bending the fins on the turbo! Once cleaned out and yet another new turbo it was fine. Good job it was under warranty at the time!

Thanks very much, that is good advice - I'll ask them to do that.  The reconditioned unit has come with a 2yr warranty, so hopefully they'd replace it if that is the case - obviously the garage would be charging me for the removal and refit unfortunately!

Good luck let us know how you get on

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[pudding]

Sounds like fitment error to me, maybe an air leak or a noise dampener missing or not fitted properly?

I once put a new turbo on a Fiat panda 100hp and after a few days it was making the police siren noise, put another turbo on and it did the same, turns out there was a lot of moisture in the pcv system and as it was winter time the turbo was effectivley freezing up and bending the fins on the turbo! Once cleaned out and yet another new turbo it was fine. Good job it was under warranty at the time!

Whaaaaaaat!    Never heard of that problem before, that's mental!