It’s easier to get at the exhaust manifold flange bolts from the bottom, did you use a new flange gasket?
Seems the flex pipe is in need of replacement, also.

 

New manifold gasket was used but I reused the old flange gasket. I will try a new one.

 

Did you get the broken flange bolt out?

 

It was a bolt on the exhaust manifold that broke off, not on the flange. #5 on the chart in post #30

 

Did you replace it?

 

I am finding different specs today. The spec I find today is 10 lb ft. The studs are 15 ft. lb.
In a different place they have the 124 ft lb number.

Don't know which is right.
.

 

I'm pretty sure Don meant 124 lb in:

these are from the HHR shop manual - 2006 ENGINE Engine Mechanical - 2.4L - HHR

Exhaust Manifold to Cylinder Head Nut 14 N.m 124 lb in
Exhaust Manifold to Cylinder Head Stud 10 N.m 89 lb in
Exhaust Manifold Pipe Flange Stud 16 N.m 12 lb ft

 

OOPS, again. I'm not sure if I trust my maths isn't that very nearly 10 lb ft?

 

I did not fix the bolt, the stud sheared off

 

Hmm. You need to extract the broken stud and install a new one. If you don't you'll end up with a manifold leak.
Probably need to take the manifold back off to gain access to that broken stud. If it broke off with enough sticking out to get vice grips on it, then it should be easy to remove.
If it broke off flush in the head then it will require an ease-out. Probably going to need a 90 degree drill head to get in there and drill the pilot hole.
Lots of patience and a good supply of bad words are required.