William, this is a classic sign of three things that will make that happen. First is the OVP relay. If your ABS light is constantly on, then the fuse is blown or the relay is bad. OVP is in the fuse box with a red 10amp fuse. ($50). Second is the idle control valve. If it is bad, replace or clean it.($200). Third is the idle control module. It is the small black box on the firewall. ($250). These three things work together to control idle speed. If one of these is bad you will get the high idle before you put it in gear. If you disconnect the two prong plug on the idle valve and get the same results its probably ok.