Xsara Picasso 2.0HDI black smoke and limited revs

[Lawrence1973]

The issue continues....
I've carried out some investigations:

Vacuum pump is working (tested the brake pedal) some one said this is linked to the turbo charger (not sure about that)
MAF was replaced a year ago - does disconnecting this test whether it's at fault?
EGR - could this be causing these symptoms? there appears to be some small solenoid devices linked to this (not sure what they do)

Seems likely that there is an air leak though- I've never heard the squeaking sucking sound before when the engine is switched off (it lasts for about a minute and gradually stops)

Anymore suggestions from anyone?

Cheers

Lawrence

[RichardW]

Is the engine management light on?

The turbo uses a vacuum actuator to control the waste gate, and the EGR valve is controlled by a vacuum actuator as well. The EGR could cause black smoke problems. Disconnecting the MAF may result in an improvement, not sure. Where did the MAF come from - cheap after market units are notoriously poor. If you can figure out which is the EGR solenoid valve you could disconnect and plug the vac hose to it, this will disable the EGR and see if that makes any difference.

[Peter.N.]

Try disconnecting the air intake pipe from the manifold, if it stops smoking you have an obstruction in the air intake/turbo/piping. In my experience failure of the MAF causes lack of power at low revs.

Peter

[Lawrence1973]

Thanks both,

No engine management light. The MAF was certainly not a genuine part.

I'm still wondering the sucking air sound, it must be related and must be somewhere on the pipework.
It's just so tucked away!

Cheers

Lawrence

[RichardW]

It could just be the AC pressure equalsing - try turning it off, and see if it still does it....

[Peter.N.]

Sucking air sound could be a restriction in the air intake, try what I suggested.

Peter