I bought a running 2.4 insurance write off to strip a few years ago and when that warmed up the idle wouldnt sit in 1 place and the rev counter would move up n down slightly.
It turned out that the the throttle body valve wasnt closing properly due to a build up of gunk, once cleaned the idle was stable.
The throttle butterfly valve is on the end of the manifold next to the egr.
Not sure about loss of power though ....

 

I doubt that would do it....they are wide open all the time (with one or two exceptions) with the engine running.....

 

Have you used MES to see if there are any error codes?

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I've just checked and there's no error codes at all. Very strange. It hasn't gone into limp mode since I posted but it has had some hesitation with the turbo and idles rough.

 

@Joesmileyface

The photo below is what I fitted. They ain't cheap (x2 more expensive) so I think I spent over 100 quid on a full set, but it was the best choice I could've made.

I was told "all 2.4s" labour to start and smoke a bit (by a "specialist" that turned out to be anything but.... they folded and went on the run...), so like I said, I changed them as a dice roll because it was really struggling to start in typical UK ambient weather, and I'd never replaced them since I bought the car (so I knew no different). Now it fires in around 3-4 revolutions, every time irrespective of outside temp. with no smoke and a much smoother idle.

I don't know if you've done it before, but just go careful and plan ahead if you plan to extract your glow plugs. The torque settings are tiny (c. 20-30 Nm as I recall) and I've certainly read of many people snapping them.

I followed the below link for guidance on an extraction process (i think I dropped engine oil onto each plug, at the base/where they thread into the manifold, 2-3 times and left it to soak for at least 1 week). They came out quite easily, but I was also very gentle/careful too.

Good luck! [emoji1303]

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