No acceleration

[Nanny]

Hi Please help
My beloved 2006 1.6hdi will rev but when I try driving I can pull off and crawl along but I have no acceleration. Any help on which tests I can do to find the fault would be greatly appreciated x

[Sol]

Its hard to say, are there any warning lights or messages on the displays? Will it actually rev past 1200 RPM when sitting in idle, or even 3000 RPM as these are "limp-mode" points which are restricted engine operating speeds set by the ECU in the event of an issue for which it determines is unsafe to run the engine at full power. If restricted to 1200 then it will feel like it will not rev at all.

Have a read of the document attached in this post, it shows the various issues which cause limp mode and what RPM they restrict you to (different faults = different versions of limp mode with restrictions to 1200 or 3000 RPM)

https://www.berlingoforum.com/thread-20797.html

[Nanny]

Thanks I have no lights and although I can get it past 2000 rpm when I change gear it goes back down. As you can tell I’m not very technically efficient x

[Sol]

No worries! It could be that you have no turbo boost, that makes the HDi feel like a snail. But it should still rev - although it would be gutless - could be a split boost hose, or many other things. 

If you knew how, I would say disconnect the MAF and see if it runs better, it is a plug on the intake tube between the front of the car to the right hand side of the engine bay near the grille, heading back to the upper rear of the engine. On that tube, is a plug which connects to the air flow meter. Unplugging that may temporarily solve the issue and let you use the car till you get it looked at by a trustworthy garage.

Looks like this, unplug with the ignition off, then start the engine and see if it works properly with this plug off (no harm can come of this)

   

If that doesn't help, you need to get someone to check for turbo boost.

[saskak]

I agree with Zion. It seems to me most likely a no functioning turbo. You could have faulty (broken diaphragm) or stuck wastegate, vacuum loss somewhere that feeds the wastegate or say for example a stuck turbo solenoid at the back left of the engine. These turbo solenoids are mostly stuck in a way that they produce overboost, rather than under boost, but you never know.
If I were you I would check when you start the engine if the wastegate arm moves at all. It should move ~2-3mm, a simple test like in here: https://youtu.be/WLsMzdKgI1o

If you have any OBDII scanner, you can check how much boost it produces.