Change the coolant sensor, cheap and fairly easy (may damage the old one getting it off with a socket...). No need to drain coolant I think, just a small leak.
Replace the damaged exhaust section, should be cheap and easy on your Punto. Avoids the lambda getting a lean (high O2) reading and telling the ECU to add more fuel.
Get the ECU fault diagnosed, it will probably give a temp or lambda sensor fault.
Replace the damaged exhaust section, should be cheap and easy on your Punto. Avoids the lambda getting a lean (high O2) reading and telling the ECU to add more fuel.
Get the ECU fault diagnosed, it will probably give a temp or lambda sensor fault.