Hi everyone, I got my 4.4 AJD 2011 RR on the Road after a project repair and have noticed that if i Accelerate hard (pedal more than 1/3 in) i get a Very High pitched Squeal from what i think is the Drivers side but may not be.

My Question is how do the Turbos operate?

i.e Variable vane operating constantly on any acceleration and Fixed vane turbo only operates at 3000RPM and up as a back up?
this may help me diagnose the problem when i strip the Hoses and inlets and more.

I don't have any faults logged in the ECU, there is no sign of smoke and power is not reduced!

Thanks
Stephen

I don't really know these engines, BUT if it only when you suddenly accelerate harder, as opposed to gentle acceleration, and you have no other faults / problems / codes, then check the belts and pulleys for various drives, before you start pulling parts off. Hope this helps.....

Gearbox clutch packs or torque converter slipping?

Merchy wrote:

I don't really know these engines, BUT if it only when you suddenly accelerate harder, as opposed to gentle acceleration, and you have no other faults / problems / codes, then check the belts and pulleys for various drives, before you start pulling parts off. Hope this helps.....

You could be right about testing whilst in neutral, but then engine is not under load.
It's just my remote guesstimate without hearing the noise. As an engineer, I would start looking at the simpler causes to a problem first first, and rule them out, one by one before you start removing parts, as it is a relatively easy thing to check. Hope it is a relatively simple problem, not the gearbox / clutch etc.

When you stated fixed belts, if you mean toothed belts ( As I said do not know these engines ) then discard my guess on the belts, but the pulley bearings can squeal as well.

Remote fault finding is never easy
A wizard with better info may be along soon

I've found this video which is very similar sounding,

the topic of the video is Boost leaks which solved the problem

&list=WL&index=2

I guess the next step is to get a smoke test done at a garage, or strip the hoses and inlet (which may not be easily visible)
There are smoke testers on the bay for £135 I'm tempted but seem a waste for single use

You could always sell the smoke tester after, there would probably be someone on here who would buy it.
Depends on how cheap you can get a smoke test for.
If your noise is virtually the same, you could be half way there already. Sounds like the way to go next.

Been talking to a local independent who has experience. Best indicator so far is that the inlet manifold is a common problem with leaks and cracks, carbon and soot will build up on the problem area. Will be taking the inlet off for inspection as its only an hour Job.