Heating and cooling issue! Need advice

[swetulpatel@gmail.com]

Hi,
I have a 09 aveo LT. last year I had a P0128 code so I replaced the thermostat( just the front metal housing with thermostat) and kept the old plastic housing that connects to engine. There are no leaks or anything.

The code went away and in summer the engine used to reach optimal temps and bust a few hoses but just like before the engine was not reaching optimal temp in winter. So i replaced the whole radiator and hoses. Now during idle at rest the engine warms up in 20~30 min. there are no engine codes BUT as soon as i start driving the engine temperature falls lower and lower in the winter and stays between 20-30 degrees celsius.

I need the heating to work since i live in a cold region( winter temps ranger from -20 to -30 degrees celcius). I believe the thermostat has failed again because during a cold start. the hose feels like it is moving antifreeze to the radiator.

There might be other issues too like the clock always resets to 1:00 am everytime the car starts. Fuel consumption is terrible(max 300km range with full tank).

Any ideas of what might be the issue?

[Eg.h2o]

I believe the thermostat has failed again because during a cold start. the hose feels like it is moving antifreeze

if this is the case, I would replace the thermostat again. Low coolant temperature would also give low fuel economy as the ECU would believe that the engine is not at operating temperature and run the engine fuel rich.

[swetulpatel@gmail.com]

Do you know if it is better to get a 221 degree thermostat or 190 degree for a 09 aveo LT

[Eg.h2o]

You have to replace it with the original temp thermostat otherwise your ECU will trip a code for incorrect running engine temperature.

[swetulpatel@gmail.com]

That’s the thing. I can’t find the normal operating temperature anywhere

[EAD15]

This is the thermostat I bought and installed in my 09 Aveo5 LT after mine got stuck open one day. I've had no codes since then and my coolant temp remains at the midpoint of the dial consistently now.

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Edit: Looks like it's a 221 degree thermostat.

[Eg.h2o]

Yup. 221 is original.

[MetroMPG]

Any update, swetulpatel? Did you get it sorted out?