Hello together My 90’s year 88 with NG-motor makes me trouble. I have already exchanged a lot like all hydros, camshaft and valve lid seals, water pump, timing belts and roller, all belt, Lufi, all ignition cables with distributor and finger, LLR however needed as well as all O-rings to the substrate carrier of the injection nozzles of the KE-Jetronic which are inserted into the cylinder head. I checked all vacuum hoses on cracks and then equipped with hose bridens. I tested the idle and full speed switches for function with a pass tester, i.e. the two Temp.-feelers up to the ones in the cooler itself are also changed. Nevertheless, it stubbornly keeps an idle of 1200u/min. in warm condition. Cold start is usually 1000u/min. as it should be. If it gets warm, approx. 50°C water increases the speed up to approx. 1400 U/min. So I never get it through the TÜV. What can that be? Could that be at the Klap pe for the cold start so that he always gets warm air? I really have no ideas anymore, you know ev. what? Would be glad.. many thanks in advance..