Loss of power

Hi All

Hoping someone can help.

I have a  2007 citroen relay 30 L1h1 100 swb manual diesel. I'm lead to believe this uses the 100 Multijet /2.2 HDi Transit MK7/ Mondeo. Hence I've come to you guys for assistance. Think it's also used on the Peugeot Boxer too.

Had the MIL come on with error code P0402. I cleaned both the EGR and the MAF. The EGR wasn't carboned up at all like I expected, just a slight coating. That made no difference.

I have now changed the EGR, MAF sensor, fuel filter and air filter. But if anything the van is worse.

It currently will hardly move from standing. Put it in neutral and gradually press on the accelerator and the revs will increase to a max of about 3000. Floor it and it won't respond.

The connectors seem ok on the EGR and MAF. However I don't seem to get a 12v reading across the EGR motor terminals at any time which I thought I would at some point to open the valve.

The exhaust seems to be blowing out the tail pipe so no obvious blockage. However, I have found the exhaust pipe seems to have split at a weld at what is possibly the CAT. It's the first box out of the manifold and on the manifold side. Split appears all the way around but the pipe is still inside the box if that makes sense. eg it's not severed off and hanging in mid air but is lose. There is no obvious roar from it either. However, there is soot around the area.

Finally, it appears to be more and more difficult to start. But gives the symptoms of a stuck starter motor. So that may be a red herring. 

This all started with when driving along, revs would suddenly increase and then drop back again but with no increase in speed. Appears to happen more when going up hills/ inclines, so under load basically.

So like I say it will now barely move.

Any help would be appreciated.