First of all sorry for the language, I'm a long time reader of the forum but only with Google Translate. I was advised by some members of the forum (Nicolas and Alexis) to write in English as I don't speak French.
I'm from Hungary, bought my Ghibli 2.0L ABS 3.5 years ago from the Netherlands. It was in a nice state, bit much kms (140.000), but with an extensive service history, except the last few years when it wasn't really used.

The only problem, loud noise, was with the Ranger differential, which I replaced with another used one.
After two years I've noticed a overfueling (oil level was increasing but not with water), and in the end found some faulty temperature sensors which I replaced, a vacuum leak in the back of the intake manifold, also cleaned the injectors and replaced the oxygen sensors. This seemed to fix the issue.
Last winter I was planning to overhaul the whole suspension (rubbers, repaint, etc.) but only finished with the rear part.


While preparing for the front, I've noticed the well documented crack on the right hand longeron.

Before doing the suspension I also wanted to verify the power of the engine, and only measured 250bhp on the dyno. So decided to wait for the next winter to tackle these problems.
This is where I'm now, and I'm writing here because I think there is a lot of relevant technical knowledge for these cars (late 2.24, Shamal, Ghibli, QP4) here. I'm still getting to know this car, and I'm not a mechanic, just doing it as a hobby, so excuse me the dumb questions I will come up.
In the last week I've finished pulling the engine, so that the crack can be fixed.


Now I'm trying to understand what could be the reason of the lack of power. Compression was ok.
When I had the issue with the increasing oil level some workshops said it's the rings and I have to overhaul the whole engine. At that time without knowing too much I just said ok, and started slowly collecting the spare parts. But today I don't yet want to open the engine because I don't think it's in such a bad state. I'll first start with diagnostics to better understand the current state instead of just replacing things. Planning to do a leakdown test and verify the timing first. I was thinking about setting valve clearances, replacing the streched timing chains which I've already bought earlier and setting properly setting up the timing. If these fixes the power great, if not I can still open the engine.
I was also thinking that maybe the turbos are tired, and while I was removing the engine now I found quite some oil in the R.H. turbo outlet - intercooler inlet. Could this be connected to a broken blow off valve? When I was looking for vacuum leaks I've found that the R.H. one had a broken diaphragm so I've also replaced that.

Peter