94 Deville Codes
 

Wondering how to clear history codes. Ive changed Idle control motor, both o2 sensors,map sensor,sparkplugs and wires. Codes show up p031,r61,r62. help and thanks

Also when I first start the car, there is no service engine soon lite,after idling for awhile it comes on. Shut the car off and it's gone,drive the car and no lite, shut car off/ start back up and idle, lite comes back on.