MY 99 SEPHIA 5 SPEED IDLE LOW WHEN COLD AND WHEN IT WARM UP TO OPERATING TEMP. THE IDLE GOES UP TO HIGH AND I FEEL THAT IT BURNING RICH. HOW CAN I FIX THIS PROBLEM. I ALREADY REPLACE THE COOLANT TEMP CENSOR . I THINK THE PROBLEM IS THE IDLE AIR VALVE BUT HOW CAN I BE SURE IAM REPLACING THE CORRECT PART.