Smells problem
2001 Chrysler Town and Country 6 cyl Front Wheel Drive Automatic 135000 miles
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When I drive the van about 15 minutes I get steering wheel pulsing and shaking which gets worse at higher speeds. When I stop I can see smoke coming from holes in rim and smell acrid smoky smell. Chrysler dealer torn down brakes and said looked like the rotor was getting hot but found no unusual wear to brakes and couldn't reproduce the problem. Likely they didnt drive it the 15 minutes or so to evaluate properly. Could this be a malfunction of the abs sensor, but I have no abs service light on. I want to sell the van but not in this condition. Help please.

caliper is not releasing
possible bad caliper and or a hose
also flush the brake fluid system