My wife's car is a 2006 Sebring with the 2.7 L engine. Normal maintenance has been done on it since we have owned it. In the last 12-14 months I have had to replace the climate control that has the upper radiator hose, heater hose and overflow vent hose attached to it in the engine bay, passenger side, next to the intake manifold. This part is garbage as it is two pieces of plastic glued together!

I just replaced it for the 6th time two days ago. Every time I replace it, the system gets bled and normally 1 to 1-1/2 gallons of anti-freeze is needed. I went to a 13 Lb relief reservoir cap on the over-flow instead of the factory 18 lb relief. The car has 153,000 highway miles on it as we live in Northern Minnesota and do a lot of highway driving. My 2000 Dakota with a 360 Magnum in it is more reliable and it has 225,000 on it!

Has anybody had this issue before? If so what was your fix or any ideas of why the system would over pressurize and not relieve through the radiator cap on the overflow tank?

 

That part is called the coolant outlet manifold. There are several long threads about it here on the forum. Some people have mistakenly called it a thermostat housing, which it is not.

There is a bleed screw on the top of it. NEVER, NEVER, NEVER touch or allow anyone to touch that bleed screw. You are right, it's a poorly designed part. The female thread that the bleed screw is in is poorly anchored to the plastic of the body of the part. It's very easy when turning the bleed screw to strip out the small flutes of the plastic which will cause the part to leak and fail.

When filling the system, air will be trapped. After a few warm-up and cool-down cycles the air will purge itself, whereupon you can top off the coolant, but in the factory or at the dealership, they don't have that option. If you want to replace the part yourself, read through the threads on the forum here for a detailed description on how to do it and what tools you will need. It's worth reading even if you hire someone to do it so you can discuss the proper method.

 

I Have to agree with you on this. The only time I have messed with that bleed screw is when I initially installed the new coolant manifold. Before I even do that, I will bleed the coolant system and use a 1/4" drive and socket to very lightly snug it. The biggest problem I am having is it develops a leak between the lower base and where the plastic mold of the upper piece is. It just seems like all the air pockets are not relieved any other way than to take it to a shop and have them hook it to a coolant recovery and refill machine to avoid the issue of air pocket problems. I am no expert with this engine but between my aircraft maintenance, powersports and marine engine background I am not mechanically challenged either, just dumbfounded that a critical part would fail so often.