Ain’t it the truth! Now on to the next… to figure out the mystery typewriter sound when going over potholes.

 

I ordered one of those filler neck for the HHR came today my question is the radiator cap does not specify the pressure the cap operates at is this been a problem for anyone?

 

It should be a 15 lb psi cap you should be ok

 

You see the picture, it has a 1.1, that is bar, which translates to just under 16 psi.

 

I saw that 1.1 had no idea what it meant thanks for the answer.

 

Thanks for the response

 

I'm so glad I came across this thread. I was about to do a full coolant flush and thermostat replacement after getting "the code" and I noticed the hose from the neck to the engine is beginning to seep. Got the replacement hoses and came here to get some more information. I then decided to replace the neck too after seeing they can disintegrate if old enough and I have no idea if mine was ever replaced prior to my ownership. But, as many have discovered, they aren't available in the stores. However, I found that both Rock Auto and Parts Geek have plenty in stock. I couldn't find the metal ones anywhere so I ordered 2 of the stock ones. Head to either website if you need a replacement. Pricing is $13 at PG and $17 at RA. I went with RA cause they have better shipping options.

 

What is "the code"? If you mean P0128 you need a ACDelco 131-158 t-stat. Dexcool has a 5 year life regardless of miles. "Flushing doesn't do much on these engines, even the radiator is aluminum.

 

Yep! I wish I had heeded the warnings by Steve and others who had posted back in 2020, but I had no troubles until trying to twist open/close the cap, and that was the start of the first crack (probably back in early 2022), then when temperatures heated up, that hairline crack opened my eyes to this - what could’ve been a catastrophe.
I found all the parts on Amazon, including the metal filler neck. It’s probably something you might want to do at the next radiator flush. I will never trust plastic filler necks ever again!