HELP had made problems with C4 1.4 16 V style

Hello, I have to say this is the worst car I’ve ever bought! My car has now 88000 KM on it, 2 weeks ago the cylinder head gasket and the timing belt had to be changed due to oil loss. Last week I had the Lambda probes replaced because the car jerks when it stands and runs out. In the display exhaust system appears defective and the small organ sign on the top left of the display lights up. In the workshop nobody can tell me what it is, after d In the labda probes they had changed the throttle valve and that didn’t work either. Now the control unit was also changed and the whole wire harnesses were checked. No success car runs restless and when it gets warmer by driving longer it goes out and brings error exhaust system defective. I am at a loss! Come to me so hard….! About Citroen Cologne, no chance, you are stupid and it is referred to the Garanie has expired! That I from the beginning on Pr obleme with the car had been dismissed as “Kalter Kaffee”!! And I should change the brand if I am not satisfied with Citroen!! Well that is called customer friendly! :-(! In addition, I had a Blaupunkt radio installed and this should now be to blame. Therefore I should bear all the costs. Am now at 2000 Euro, and car simply does not work. Who can help me or knows this problem? HELP …