P0136, P0141(Sensor Heater Circuit Malfunction) Mits Eclipse

Hello
I have a Mitsubhisi Eclipse 2001 GT and from the past couple of days its showing "Service Engine Soon" light. I did a scan using OBD scanner and it shows P0136 and P0141 codes. I would appreciate if somebody could help me out to crack those codes.

I have also noticed that engine heating needle is shooting up pretty frequently. Is something wrong with the radiator or do I need to change the coolant ?

Kindly advice so that I could get rid of the "Service Engine Soon" light.

Thanks!
~T

P0136 = O2 Sensor Circuit Malfunction (Bank 1 Sensor 2)

P0141 = O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)

Your post-cat O2 Sensor may have quit working. Before condemning the sensor, check the wiring and connections to it, check for voltage and grounds and check all fuses.

As for your temp. guage, is the vehicle using/leaking any coolant? Is the coolant level low? When was the last time the cooling system was flushed and the thermostat checked/replaced? Will your scanner display engine temp?

Good luck and keep us posted.