Plugs/wires/engine and transmission mounts/ battery + TB cleaned. Now runs so smoothly that passengers ask if engine is still on. Used to run that way even from cold start. Now, before warm, engine runs rough & idles fast. PCM idle relearn needed?

Try replacing the ECTS. This is located on the driver's side engine block, under the EGR valve. The sensor connector will have two wires connecting to it. This sensor pays akey role in the performance of the engine. It seems data to the PCM for air/fuel ratio. Poor idle, stalling, high rpms after starting engine at normal operating temperature, poor fuel economy, and loss of power are all symptoms of a bad ECTS. Replace this sensor. There is also a sensor very close to this one, above and to the left of the sensor needing replacement, it controls the temp gauge on the cluster. Don't replace this unless your gauge isn't working. Make sure you replace the sensor that has two wires on it. This part will only cost you about $15 and will take about five minutes to replace. Give this a try and please let me know if it has helped any. Good Luck.