D5 (D5244t I think), slow pick-up and whistling

[R-P]

Thanks Matt,

What I did try is unhooking the governor completely. It then also misses out on the very much present 1800rpm kick-in-the-groin-boost. So the governor does *something*.

The arm is also moving (only checked with direct vacuum), but that doesn't mean anything, does it? The vanes could still be stuck?

+ YouTube Video

[Bernard333]

There are 13 individual vanes in the turbo each operated by a lever that looks like a small bone , the ends of the 'bones' are driven by a large ring which is moved by the vacuum actuator arm via a lever . I have heard of the large ring cracking so that the actuator arm whilst still moving is not opening any or all the vanes but reading your posts you are getting turbo boost ? The whole variable nozzle mechanism is quite a loose fitting affair but subjected to a lot of heat and possible soot build up . Checking the turbo rotor for play is easy without removing the turbo but unfortunately to check the variable nozzle properly you would need to remove the turbo and split it open . I removed the turbo from my D5 only to find there was nothing wrong with it other than slight wear on the thrust bearing so it went back on the engine having done nothing to it . You can buy a replacement variable nozzle for the turbo , even the aftermarket people are making copies now but I am not convinced this is your problem . Most turbo failures are due to poor oil supply causing the large thrust bearing to wear rapidly then the rotor waggling about hitting the outer casting does the rest , or the internal oil seals failing allowing engine oil into the induction system .

[R-P]

Originally Posted by Bernard333

There are 13 individual vanes in the turbo each operated by a lever that looks like a small bone.

Aha!!!

I thought the 'bones' in your pics WERE the vanes, but I guess they are simply not visible in those pics...

I was pretty disappointed at the shape and size of what I thought were the 'vanes'

I am learning something new every day
http://www.volvoforums.org.uk/attach...9&d=1276606414

[Bernard333]

You can just about see some of the ends of the vanes poking out down the inner part of the casting . I think the vanes serve a very similar purpose to the wastegate on previous generation turbos but are more controlable giving a more steady boost over a wider rev range . The variable nozzle complete in the photo is all ok despite looking manky and opens and closes nicely with no chips in the vanes which is just as well because even the non Garrett variable nozzles are over £100 , the main problem with this turbo is the failed oil seal and thrust bearing but it is repairable . The other turbo I wanted to repair I have decided is too shot as it needs a new impellor and main shaft , but even for this situation you can buy oversize bearings , but a new bearing/seal set plus new rotor comes to £150 and good condition complete turbos come up on ebay for a lot less .

[S60D5-185]

Originally Posted by Bernard333

a new bearing/seal set plus new rotor comes to £150 and good condition complete turbos come up on ebay for a lot less .

Best and easiest way to go if you get a GOOD one.

Darryl

[REDSHEEPRIDD]

I have a 2005 MY XC90 D5, which although I have no fault messages, it has been running a bit noisy and has an annoying vibration(buzz) through the pedals/floor on acceleration (especially slow speed) and when I select reverse idling.
Garage says mounts appear ok - but having read this thread, can I test the vacuum lines etc (can see them running from box on side of air filter) - I am not overly technical and do have any guages etc - so is there a simple check.

[R-P]

Just to add: finally got my hands on a MAF sensor and replaced it today. I don't think anything has changed.
Either this thread or on some other forum it was suggested that the MAF could still be the culprit, also because I *think* the slow pickup was also present with the old engine-block and the new engine-block was put in including the injectors, vacuumpump, governor, turbo, etc., so either both turbo's had the same problem (...), or the problem was outside the engine with all its attached components.

Therefor the MAF wasn't a bad guess: that stayed the same during the engine swap.
I did notice an oily substance in the MAF sensor ????? There shouldn't be oil that far UP the airinlet should there?

Guess the next step is to unbolt the turbo and take it apart...
But as this is the only car we have (can't afford more cars with a roadtax of 1750 quid a year...), I'm going into the hospital for 6 weeks very soon, and the car still has TWO leaking AC-radiators (and we had 25ºC today...), this is somewhere in the bottom of the "to do" list...

As for testing the vacuumlines: it's hard to test them without a gauge. You can unplug the line going into the 'switch' on the airbox and simply stuff a bit from a screwdriverr bitset in the line. Then drive around and see if you can notice the mounts NOT stiffening up below 1500rpm. If you feel a big difference, then you know it normally works OK, but this is a very inefficient way of testing this

[Lancee]

Have you seen the post about the blocked filter on the turbo governor ? Not sure if it's relevent to your problem or not but you may want to dismiss it by a process of elimination.

It's inside the black box you refer to as quoted from your listing below.

"The black-box on top is the air-inlet for the environmental pressure. The white thing on the right is where the vacuumline and the output to the turbo are hooked up. The tear is clearly visible at 6 o'clock in the middle of the red membrane."

[R-P]

Thanks Lancee, but I replaced the one with the ripped membrane for a new one (not another used one, but an actual new one, so I doubt the filter is blocked). Made no difference, so even the tear didn't do any noticeable 'damage' to the performance of the engine...