Questions & Answers for: Pontiac Grand Prix code p0128

...P0128 code is to indicate a faulty thermostat. A code P0128 may mean that one or more of the following has happened: Low engine coolant level Leaking or stuck open thermostat Faulty cooling fan ...

code P0128, P0420, and P0455 popped up trying to figure out what these codes mean and what I need to fix on my car P0128 ECT Sensor Below Thermostat Regulating Temperature P0420 Catalyst System Bank 1

HELP ME WITH THESE CODES!! I went to autozone because I felt my car very weird, when i step on the gas the shifts feel very rough but when its running at a steady speed it runs very good, and when I ...

...P0128 is an insufficient coolant temp code. Which means the coolant temp is not coming up to full operating temperature fast enough or not at all. The fix for this is to replace the

obd2 code po 128 obd2 code reader says po 128 P0128 means that your engine thermostat is more than likely faulty. The code description is engine operation below thermostat regulating temperature.

HELP!! Many codes.. My car has a problem with the engine light and the Reduced Engine Power lights. Today I took it to P0128, P0171, P1125, P1516, P2125, P2138, and U0107. The car has a new gas cap, a