PimP in distress....

1990 riviera cold starts fine but immediatley jumps to 3000 rpm. Just replaced the TPS sensoior and still does it. Any suggestions. My spedometer has a mind of its own, zero sometimes, it wont keep track of my speed jumps randomly and stays at zero sometimes. Is this a BCM module and if so were is this thingy located. Also should the bcm be drawing constant power or does it shutdown completely, because mine dosnt.