My sister got a code P0128 on her 2002 Pontiac Sunfire GT.
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 (running too much)
* Faulty coolant temperature (ECT) sensor
* Faulty intake air temperature (IAT) sensor
First thing she did was check the coolant level in the reservoir tank. It was low so she topped it off. Does anyone have a photo of the cooling system bleeder valve location on a 2002 Pontiac Sunfire GT? I have found a couple of photos of the 96/97 Cavaliers but it doesn't seem to be similar. I'm hoping that after she bleeds the system and tops it off again that the code will be gone but I figured that while I'm here I would ask a few questions.
If it does turn out to be a thermostat, I know it's located on the back drivers side of the motor. I have read where the manifold has to be removed if it's an automatic car but her's is a manual transmission. Is it possible to replace the thermostat in this car without removing the exhaust manifold?
Nope you'll need to remove the exhaust manifold to get to it. Pretty good engineering, huh ? I had an 84 sunbird and the thermostat was right there when you removed the radiator cap, simplest setup I've ever seen, don't know why they can't stick with something like that instead of removing the exhaust manifold to get to the thermostat, sounds ridiculous to me.
The coolant was low so I had my sister top it off. She let the car idle for 15 minutes after topping off the coolant and the car barely got up to temp. I had her let it run for a total of 15 minutes. She sent me a picture of where her thermostat is at. It was sitting at about 115. Does this seem like the cooling system needs to be bled or most likely a thermostat?
After driving it for 20 minutes she said the temp went up to 195. I can't figure out where the bleeding valve is. I can't see the actual car in front of me since she is in college in vegas and I'm in MD. And I can't find a service manual for the 2002 Ecotec.
My 01 z24 did the same thing with the temp barely climbing after driving for over 15 minutes thermostat was stuck open, replace that i'd say