Why 1998 Buick Regal LS lower radiator hose collapses when throttle is being pushed
Pull the rad cap off (when the fluid is cold) and check the fluid level in the rad. If the rad is full check the cap. It should hold pressure up to it's rating (stamped on it) but the center should open on very low vacuum to draw fluid from the coolant reservoir. Check the hose from the rad to the reservoir, may be plugged. Worst case is plugged cores in your rad.
Ditto on what beer stated Have you ever replaced the hoses?
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