Turbo not working properly

[MrYesNo]

Hi everyone,

My 1999 HDI 110 has started developing problems. The turbo has started taking slightly longer than normal to spool up if I'm starting from low revs. But the weird thing is that if I'm driving along at a steady speed and I'm at about 2000 rpm, if I put my foot down, I get what seems like almost no power at all until I reach 3000 rpm, when I suddenly get a surge of power. I've got the torque app, and the MAF seems normal, there are no fault codes, and when I experience this lack of power between 2000 and 3000 rpm, it's telling me I'm getting about 3 extra psi instead of 15 which I had until recently.

Any ideas? Is my turbo knackered?

[GingerMagic]

Mine was a bit lethargic until I swapped my turbo electrovalve for one that worked and its now all better.....

A duff EV may not show any faults but if it leaked vacuum or was disconnected then you would get a message pop up on the clock display.

Turbos rarely go wrong, its normally a vacuum leak or a EV failed.

While you've got the bonnet up, check the slack in the throttle cable - if this is okay then unplug the MAF and do a test run, you will get an fault flash up but it will go out again in a few trips after reconnecting the MAF.

[MrYesNo]

Thanks, GingerMagic.

I've disconected the maf sensor, and it behaves exactly as before.

My new theory is that it could be a sticky EGR valve. I've checked that the EGR valve doesn't leak. However, there's quite a lot of carbon deposits around it, and I wondered if it's just failing to close when I put my foot down at 2000rpm. I'm presuming that if I'm cruising under light load at 2000rp, the EGR would be open. And it would need to close when I put my foot down. Failing to close straight away would give me the symptoms I'm describing, no? I can still hear whistling from the turbo even though I'm getting very little power.

Does that make sense? If so, would some EGR cleaner help?

Once again, thanks for any advice.

[GingerMagic]

To be perfectly honest, I don't know much about the EGR, I know what it does but not really how it opens/shuts at a given time.....

Have you looked at the vacuum pipes from the EGR to the EGR EV to see if its split? I know some EGR stick open, some stick closed but how you can tell without surgery I don't know.

I've always just blanked my EGR anyway to avoid my engine choking on its own carbon and soot...

[Doggy]

Could also be a boost leak. Check all the hoses between turbo, intercooler and inlet manifold, either by listening for the sound of escaping air, or look for signs of oil seeping from any of the joints.