2013 Sonic 1.8 60,000 miles. Just replaced thermostat, now ac blowing blowing hot air and check engine light is on. Freon levels are good. Did some research and found that if you remove negative battery cable and let set for 5 minutes, light goes out and cold air blows. Problem comes back 2 days later. Nowing that this is electronical and not mechanical. Any ideas as to what is the cuase and how to fix.
AC blows hot air
- Thread starter BLand
- Start date
TurtleOverlord
Active member
What is the engine light code?
A P0128 is a code is an indication of a faulty thermostat or ECT (engine coolant temp sensor). The manufacture designs the engine to run at a specific operating temperature for the most efficient operation. The thermostat regulates the coolant between the engine and radiator.
I had thermostat replaced.. then immediately had problems with ac. Could this be related?
I had thermostat replaced.. then immediately had problems with ac. Could this be related?
yeap...
could be faulty sensor, faulty wiring damaged wiring, or faulty t-stat .. basically engine isnt warming up properly or reading properly , takes a few cycles usually to pop up the code..
aftermarket sensors are notorious for this, and the resistance barelly being acceptable. my jeep as an example unless it was OEM electronic parts the jeep did weird things ..
or could be something simple as an airlock at the sensor, but thats not very common anymore on vehicles..
could be faulty sensor, faulty wiring damaged wiring, or faulty t-stat .. basically engine isnt warming up properly or reading properly , takes a few cycles usually to pop up the code..
aftermarket sensors are notorious for this, and the resistance barelly being acceptable. my jeep as an example unless it was OEM electronic parts the jeep did weird things ..
or could be something simple as an airlock at the sensor, but thats not very common anymore on vehicles..
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I probably should not admit this, but when I did the thermostat on my two 1.8L Sonics, I did NOT replace the temp sensor. Aftermarket is maybe OK, but its either the new sensor is bad or one of the connections are bad. Maybe some coolant is in the connector - not too hard to check.