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post #1 of 19 (permalink) Old 12-03-2013, 07:54 AM Thread Starter
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Coolant / Thermostat Problems

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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post #2 of 19 (permalink) Old 12-03-2013, 08:14 AM
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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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post #3 of 19 (permalink) Old 12-03-2013, 08:41 AM Thread Starter
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Quote:
Originally Posted by BankerBalt View Post
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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post #4 of 19 (permalink) Old 12-03-2013, 08:50 AM
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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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post #5 of 19 (permalink) Old 12-03-2013, 09:04 AM Thread Starter
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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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post #6 of 19 (permalink) Old 12-03-2013, 09:35 AM
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That may work too

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post #7 of 19 (permalink) Old 12-03-2013, 09:41 AM Thread Starter
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Well Ill check the chain then do the reservoir. I have a scanner running in my car so I can just clear the code.

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post #8 of 19 (permalink) Old 12-03-2013, 10:32 AM
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The only way to properly burp the car is to have it running with the heat on all the way up.
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post #9 of 19 (permalink) Old 12-03-2013, 11:00 AM Thread Starter
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Yep I've had it all the way up and all the way hot the whole time.

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post #10 of 19 (permalink) Old 12-05-2013, 07:40 AM Thread Starter
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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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