I had the turbo rebuilt and this started to happen immediately.

When I start up it feels low on power and then when I rev it to around 1500 2000 rpm, I hear a metal screeching noise and I get full boost immediately.

As soon as I idle I get reduced engine performance and it only revs to 3000.

If I stop completely and idle for a second (only if the car is not moving!) and rev it again it makes that whistling noise again and get full power again... until I idle again.

Can anyone help me diagnose this problem?

I took the clip off the turbo actuator and the turbo veins seem to be very smooth and don't get stuck anywhere. I think it might be the actuator itself but what the hell is that screeching metal noise when I rev it?

As the problem started "immediately" after the turbo was rebuilt (and presumably it wasn't doing it before) then Id ask the company for comment. Jules

Same turbo actuator? Did they calibrate it after the rebuild?

Yeah, id be asking the guy that rebuilt it rather than on here!

Today I unclipped the turbo actuator arm from the turbo (wire connector still connected) and put a ziptie so now the turbo veins are always open and it's not going into limp mode anymore when it idles!

I will probably leave it like that but I really would love to know what the hell that metal screeching noise was. I am 99% sure it can't be the actuator itself cause there's nothing in it that can make that kind of noise. I think its from the turbo but i'm not sure.

Its like rusty metal door opening when I rev it from 1500 to 2000 and then full boost instantly... its a mystery

Grue wrote:

Same turbo actuator? Did they calibrate it after the rebuild?

Yeah, id be asking the guy that rebuilt it rather than on here!

Roltek wrote:

T

I am 99% sure it can't be the actuator itself cause there's nothing in it that can make that kind of noise. I think its from the turbo but i'm not sure.

The sound is too loud to be coming from the actuator. I have disassembled it and I saw the worm and gear mechanism.

Yes thats exactly right you cannot move the arm if its still connected.

Usually I'm alone when working on the car so I will take your suggestion and see if the actuator moves normally when someone is revving and idling the car.


The more I think about it I'm realising that probably the actuator is getting stuck and then when I rev it, it gets suddenly unstuck and maybe the screeching noise is the veins themselves? I don't know if that's possible I'm not an expert but I'm pretty sure that the noise is too loud to be coming from the actuator.

Have you had the Turbo off to check for signs of damage, if the screeching was something touching and rubbing it will be nice and shiny.

From your description, it sounds like the vanes are touching something or encountering a foreign/misplaced object when operating. FL2 XS SD4 Auto 2010 2012-2017 (21k - 91k miles) (MY2011)
FL2 Metropolis SD4 Auto 2014 2017- (16k - 82k+ miles) (MY2015)
Metro in its 11th Year of (Extended) LR Warranty / Full LR Service History
(Expensive, but Trouble/Worry free - hopefully?)

No its too much of a pain to take it off. But if there was something rubbing or misplaced I would think that it would make noise all the time not just at this very particular instance.

I think I will just leave the actuator disconnected from the turbo and leave the veins open all the time with the ziptie and call it fixed