Question

I have an error P0125 code on my 2003 Pontiac Vibe 1.8 AWD is on after replacing the 1st oxygen sensor. The coolant sensor was also replaced.

Answer 1

P0125 Insufficient coolant temperature sensor for closed loop operation

Beside the thermostat and the 02 sensor for causing this code, the fuel pressure  has to be checked , if the fuel pressure is low you can also set this code condition , and beside low fuel pressure also check for any vacuum leaks that can also set this code condition

Answer 2

P0125 PONTIAC Code - Insufficient Coolant Temperature for Closed Loop Fuel Control
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