Hi, I have a 2002 envoy with the rear air ride suspension. This is my first winter with it, and am finding it must have moisture in the lines. When it warms up to 40-50 degrees, it works fine but in colder temps it won't raise up. The compressor kicks in but won't raise up till it warms up. Any ideas on what to do like bleeding the lines or replacing the lines. I don't really want to convert it to springs since I haul a trailer with it during the summer.