The Ecu then sends commands to the fueling and ignition systems according. If the sensor is faulty and thus sends incorrect , or no info to the ecu as above, the fuel and air mixture will be incorrect and thus do as you describe resulting in poor running and no start situations...
If you remember the old auto and manual choke systems...it works like that , only electronically. If and when the choke was in the wrong position for the temp of the engine, the engine either wouldn't start or coughed and spluttered... exactly the same.
So, without the aid of plug in diagnostics at the moment and the results thereof - its well worth renewing that sensor. Its usually located on the inlet thermostat housing , inlet manifold or thereabouts depending on model and has a two wires pin connector going to it.
Always buy one from a dealer / genuine unit. If you are unsure as to its position - ask the parts dept; when you are in there, to show you on the screen where it is located or I can look it out for you..
Fit that and all should be well again ;)
I Sincerely XXXXX XXXXX have helped you - Please ask me if you need more help...
Kind Rgds, MIKE
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