SSgtYoungGW

Hey all this is my first call for help. I have a 2008 HHR SS 5 speed with 112k miles on it. A couple of weeks ago as i was driving i noticed my car just didn't feel right. I checked all the gauges and they where all good. The car felt a bit like the exhaust was plugged. I hammered down on it and she felt good. But as i was doing this i was also watching the gauges and my boost gauge was showing almost 26 lbs of boost. I slowed down and kept watching the gauges. A few seconds later my temp gauge started to go up. I pulled over right away and turnd off the car. The gauge continued to climb tell it was maxed out. Towed car to shop and coolant was low. Filled coolant then test drove car and it overheated again. Changed t stat overheated again. Did leak down check on cooling system and it held at 18psi. Checked for exhaust in coolant and it was negative. The car continues to overheat. I did notice that even when the care is hot my heater is blowing cold. My heater has never had a problem. Also one of the radiator is also not heating up as it should. I could really use some help on this. My wife blew the motor in our dodge ram a few days after my car overheated. Im thinking about just taking that lemon to the scrap yard. But my HHR SS is worth saving. Any help would be greatly appreciated. Thank you all.

RJ_RS_SS_350

to the forums!!

ATTENTION ANYONE WHO READS THIS keep your DIC(DriverInformationCenter) set to the digital coolant temperature readout!!! There is no other information as important as the coolant temperature.

Not at all picking on you Sarge, there have been many who have come here and possibly destroyed their engine because they trusted that grossly inaccurate gauge. Or were more concerned with their MPG, or whatever.

Does the ECM have an aftermarket tune? 26 psi is badly overboosting on a factory tune.

If only one of your radiator(hoses, I'm guessing) is hot, then your radiator is plugged.

If the cooling system held pressure, but the coolant is escaping white operating, you may have a warped head that only leaks when it gets hot.

The engine coolant flows through the turbocharger to cool it. It could potentially leak coolant directly into the exhaust.

Oldblue

The oil cooler can have a coolant leak also.

I’m thinking air in the cooling system, probable cause of the heater core not heating.
Also a possibility is the water pump has either an impeller problem or the balance shaft chain broke.
then there’s the fan assembly and possibly the radiator plugged theory.
What thermostat did you install? What coolant did you use?
Did you burp the coolant?

SSgtYoungGW

Hey Oldblue, thank you for the quick reply. On the thermostat. It was my father-in-laws idea to swap it out. I never thought it was the problem. Its so rare for one to go bad. I personally have only seen it once. But i do know the oem was used. A friend of mine has recommended we remove the t-stat and see if that solves the problem. As of now i am using 50/50 mix of antifreeze. I knew about the need to change the coolant every 5 years but somehow forgot about it years ago. The coolant that was in it was original. Now that i know i need to do a drain and flush do you recommend anything to accomplish this?

Question on the water pump. I have looked up a new pump and found they are not to expensive. That and the tool is still in my price range. My question is would i need to pull the engine to replace the water pump? I was looking at it yesterday and didn't see a way to get the tool on let alone get the pump out.

Again thank you for your reply and help. Im eager to hear what you think.

With Respect,
Young, G.W.

Lonwane

As you may know, the tool holds the chain and gear in place while the pump in removed.
There is a cover plate to access the bolts for the pump and to install the tool.
Passenger side, upper rear of timing cover.
Also the t-stat housing needs to be removed (unbolted from the block).
There are videos that can show you this procedure.

Oldblue

I replace the chains as I replace the water pump. I haven’t had the howling problem so have reported, less risk of breaking the chain to!
You don’t have to pull the engine.

donbrew

Here is a tutorial on the water pump.
https://www.chevyhhr.net/forums/how-...acement-56476/

SSgtYoungGW

Thank you so much for the info. I didn't see any way the pump could be changed with the engine in the car. Thank you for setting me right on that. But please correct me if im wrong (and it won't be the first time) i thought when the coolant was flowing up and out of the fill port on the hose that it proved the pump was working. Also i thought when i got a negative when i checked for exhaust gasses in the coolant and had no pressure drop during my leak down check it meant the head and head gasket was still good. Was i mistaken? Also is there anything i can do to confirm the pump is the problem? Thank you for you continued help.

Oldblue

I’d just burp the coolant system a few times , water pumps don’t fail often.

https://www.chevyhhr.net/forums/how-...-system-60614/

You did say you installed an AC Delco 131-158 180 degree thermostat, but could you confirm the coolant, you said 50/50, Dexcool? Or that green stuff!

donbrew

He said OEM, not 131-158. As we know dealers sell the cheap one.
And a hint: At least at NAPA the parts book identifies many parts as "OEM" because the "work" the same as OEM.