This has also happened to me in the past on my 98EX, I took the panel off and used some white lithium grease on the track and put the window back on track and tightened up the 10mm bolts at the top and bottom extra tight. Never had a problem thereafter.
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Custom Vinyl Graphics/Stripes and Powdercoating
2007 Trailblazer SS 400hp/400tq
2001 Honda Civic EX
1997 Dodge Viper GTS Built and Tuned by Underground Racing Paxton Supercharger, built engine, stage 3 heads, custom cam, Roller Rockers, Bellenger Headers, Hi-flow cats , Corsa , UGR twin fans w/polished shroud, Mc Leod twin disc clutch&flywheel, AEM EMS, UGR Fuel System w/billet rails,3 walbro 255 HP pumps on billet hanger, twin crank case ventilation system, Water Meth 15-17 lbs boost