I have a 2004 Hyundai Elantra. The heater will put hot air out at high RPM, but cold air at low RPM. The check engine light came on, had a code of 128. I replaced the thermostat and engine coolant sensor, had the light turned off. 4 days later, the engine light is back on with a 128 code. Heater, same condition as above. Do you have any suggestions as to what the cause is?Thank you in advance.
have the same problem?
Wednesday, December 28th, 2011 AT 11:08 PM