Ask a Mechanic Online and Get Answers to Your Car Questions
Hello and thank you for using just answer! My name is XXXXX XXXXX I will try and help you with this problem. I do see this occasionally..
Just need a little information first. If I understand you correctly, you are trying to ready the monitors in the vehicle as to pass state inspection? Do you know which 3 monitors wont ready? Also, have you replaced the thermostat or coolant sensor in this vehicle?
2.7L engine, yes on monitors need 5 6 7 Have not replaced thermostat
or coolant sensor will do now. Will let you know.
replaced the thermostat or coolant sensor.
Drove 25 miles still the same.
I have been driving for 400 mile it did change form 4 out of 7 now it's at
5 out of 7 for 200 miles stall has hot change must have 6 out of 7 to pass
Back one more time.
Ck engine light come on code P0128
we did replaced the thermostat and coolant sensor.
Ive been doing a lot of research on this, and I can find nothing. Sometimes there is a TSB issued to reprogram the computer, but not in this case. Replacing the thermostat and sensor always repairs the issue. Check the harness/plug at the coolant sensor as this can sometimes be an issue. Here is the code description right out of the Hyundai service manual.
P0128 Hyundai Engine Coolant Temperature Below Thermostat Regulating TemperaturePossible causes - Leaking or stuck open thermostat- Low engine coolant level- Insufficient warm up time- Faulty engine coolant temperature sensor- Engine coolant temperature sensor harness is open or shorted- Engine coolant temperature sensor circuit poor electrical connection Tech description If cooling system is not leaking and the fluid level is OK, replacing the thermostat usually takes care of the problem. What about the obd code? If the Powertrain Control Module (PCM) detects the calibrated amount of air flow and engine run time have been met, and the Engine Coolant Temperature (ECT) has not met the minimum thermostat regulating temperature, the code P0128 Hyundai will set. Symptoms- Engine Light ON (or Service Engine Soon Warning Light) P0128 Hyundai Description
An Engine Coolant Temperature (ECT) sensor monitors the temperature of the coolant. This input is used by the Powertrain Control Module (PCM) for engine control and as an enabling criteria for some diagnosis.
The air flow coming into the engine is accumulated and used to determine if the vehicle has been driven within the conditions that would allow the engine coolant to heat up normally to the thermostat regulating temperature. If the coolant temperature does not increase normally or does not reach the regulating temperature of the thermostat, the diagnostic that use ECT as enabling criteria may not run when expected.