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Discussion Starter #1
I'd been getting code p0128 and my car was running too cold like the thermostat was stuck open so I replaced the thermostat with an OE exact part and now I'm having serious issues... First off, the heat doesnt work. Second, I guess there is air in the system because the coolant readings are all over the place. It read 278 last night and there's no way it was actually that hot. I tried filling it from the radiator hose off the engine and then running it with the cap off and squeezing the hoses to get air out. Had to add a lot of coolant so I figure a good amount of air came out but it still has the same problems. A friend suggested I may have bought a faulty thermostat but I wanted to see what you guys think before I replace another one. Also when I turn the car on i get p0125 for coolant temp below threshold for closed loop yet one of the gauges in my car reads open/closed loop and it is still going to closed loop.

Thanks in advance.
 

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How many miles? Have you replaced your water pump? How long did you let the system burp itself? If it said 278, it was probably 278. Did your fans come on? Did you feel the lower radiator hose? Was there pressure?
 

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How many miles? Have you replaced your water pump? How long did you let the system burp itself? If it said 278, it was probably 278. Did your fans come on? Did you feel the lower radiator hose? Was there pressure?
66,700 miles, original water pump. Let it burp for almost three hours the first day and almost two the next day. Fans come on at 214 and 220ish and stay on like they should. Lower radiator hose had a lot of pressure but wasn't hot.
 

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Dumb question but was the car running? Lol. Not sure if it matters a lot but did you put the thermostat in the way its supposed to? Pull your water pump cover on your front cover, all 10mm bolts, remove 3, loosen 1. See if the chain is still on and tight. If all that is good, remove battery cable for 30 mins and see if the code comes back
 

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Lol it was running to burp it. It seemed to only fit one way and there was a notch on the black part that I matched up. I'll check the chain. I saw someone with an lnf saying to loosen the reservoir and disconnect the hose that goes to the top of the valve cover then fill the reservoir till the coolant comes out the nipple on the valve cover, you think I should try that?
 

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It was a faulty thermostat... tried everything and finally bought another thermostat and put it in and now its perfect. Total waste of time but at least its fixed. Couldn't even tell you how much dexcool I went through lol...
 

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Was it still getting hot with the bad thermo??

---------- Post added at 10:37 AM ---------- Previous post was at 10:37 AM ----------

That's pretty strange.....
 

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I had the same problem. Bad thermostat cost me a few extra gallons of Dexcool... Replaced the water pump, and the thermostat at the same time. Thought I had done something wrong. Replaced the thermostat again, and everything worked properly.
 

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Quality control aint what it used to be fellas. I guess you gotta boil some water with a thermomater & check it yourselves. Chinese water has so many pollutants in it maybe their water won't boil, lol........
 

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I'm having p0128 right now....49896 miles

In NYC right now it's 30s to 40s

I placed my hand on engine and it was cold....While running! I noticed (and read) the fan stays on....

Soooo...before I take it in for fixing I took out the cool fan 1 & 2 relay and fuse, respectively.

Was that a good idea?

I mean avg temp now is 35°
 

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I would imagine that your thermostat is stuck in the closed position, meaning the wax pellet was unable to move to allow for coolant to pass through after your temp reading of 150.

If your DIC states under 150 degrees for engine temp, then its vice versa. The pellet stays open and never closes. That's more than likely the thermistor in the ECT sensor stuck and check for the voltage. Should read around 1.6-4 volts.
 

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Replace it yourself... you'll lose some dexcool. Get some more, find a 10mm and remove it. Then just put new one in and youre good
If I change it myself. How do I "bleed the air out of the coolant system"?

Will that turn off the end light?

Also on a 1-10 scale (1 being easy) how hard or easy is the job?

---------- Post added at 07:41 PM ---------- Previous post was at 07:35 PM ----------

I would imagine that your thermostat is stuck in the closed position, meaning the wax pellet was unable to move to allow for coolant to pass through after your temp reading of 150.

If your DIC states under 150 degrees for engine temp, then its vice versa. The pellet stays open and never closes. That's more than likely the thermistor in the ECT sensor stuck and check for the voltage. Should read around 1.6-4 volts.
It's funny because now that I removed the relay and fuse to coolant fans 1 and 2 my coolant temp doesn't say --- anymore....

It starts at 57° wen i start the car n works it's way to 145° as i drive then goes back to --- then it comes back on around high 180s and wen I stay idle at red lites it rises to 200

Slower driving it got to 221 and I was home thankfully.

Mind u this is all wit the fuse n relay pulled.

Now it's snowing n cold out

Keep the fuse n relay out?
 

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Its not hard. You have a few hoses and wires in the way, but its two 10mm bolts to take the housing apart. Drain your coolant from the radiator first a little bit. You bleed it by keeping the coolant cap off and let the car idle for a few mins
 
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