collapse upper hose
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Pro
Joined: Mar 2004
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From: Waddell Arizona
collapse upper hose
Has anyone had this problem? I just bought a 99 coupe. When I was checking over the car I notice the upper radiator hose was collapse, just in the center. I took the car to the dealer and they told me to check the level of the anti-freeze. If it is low that could cause the problem because of the vaccum in the system. When the car is started the hose goes back to normal size. 
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Good info to know. 
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Thread Starter
Pro
Joined: Mar 2004
Posts: 640
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From: Waddell Arizona
Thanks for all the help
I check the level of the coolant its ok. How do I check the cap ? Also the car only has 34,000 miles on the car do I really need to have the system flushed? Does anybody know how to bleed the system to remove the air?
Thanks, Grunz
Thanks, Grunz
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Joined: Nov 2003
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From: Mustang OK
Your dealer should have a testor to test the cap to see if it is holding and releasing pressure as it should. But, with you car going on 6+ years old, it's most likely past time to replace the cap and as E-T mentioned, it's very likely the source of your problem. Too, it appears it may be past time to drain and flush the cooling system. The cooling system in your vehicle was filled at the factory with DEX-COOL® engine coolant. This coolant is designed to remain in your vehicle for 5 years or 150,000 miles, whichever occurs first, if you add only DEX-COOL® extended life coolant. The 2003 GM Service Manual says to use only GM Goodwrench® or Havoline® DEX-COOL®. You should find more info on this topic in of your owner's manual. Good luck. 
Burning Brakes
Joined: Oct 2003
Posts: 1,106
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From: Foresters Falls(near Ottawa) Ont
Originally Posted by grunz95
Has anyone had this problem? I just bought a 99 coupe. When I was checking over the car I notice the upper radiator hose was collapse, just in the center. I took the car to the dealer and they told me to check the level of the anti-freeze. If it is low that could cause the problem because of the vaccum in the system. When the car is started the hose goes back to normal size.
Sometimes cleaning the cap with a good strong stream of water will help. On a conventioanl rad cap, you can check the vent valve with your finger nail, not sure about the screw on cap the C5 uses.
RonJ ...
Burning Brakes
Joined: Mar 2004
Posts: 1,105
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From: Richmond Virginia
Originally Posted by RonJ
The cap vent isn't opening when the coolant cools down. This creates a low pressure in the system, and instead of drawing coolant back from the reservoir, it collapses the upper hose.
Sometimes cleaning the cap with a good strong stream of water will help. On a conventioanl rad cap, you can check the vent valve with your finger nail, not sure about the screw on cap the C5 uses.
RonJ ...
Sometimes cleaning the cap with a good strong stream of water will help. On a conventioanl rad cap, you can check the vent valve with your finger nail, not sure about the screw on cap the C5 uses.
RonJ ...
Try this before going to the stealership.