After 10 yrs., this Frontier is about to drive me crazy. Had to change the alternator about 8 months ago, and have done the drive cycle atleast 8 times to get it to pass emissions.
Have wondered if my ECM is losing it's memory. Had a friend hook it up to his computer today, and it said it couldn't communicate with it. The scanner I have shows 5 readiness monitors not ready. OXYGEN SENSOR MONITOR,
CATALYST MONITOR, HEATED CATALYST, OXYGEN SENSOR HEATER MONITOR, and EXHAUST GAS RECIRCULATION (EGR) MONITOR.
One place I saw said, "If the Oxygen Sensor Heater Monitor is not ready, check to see how many other Monitors are not ready. If the Oxygen Sensor and Catalyst Monitors are also not ready, the most probable cause is a weak battery. If your Battery is 48 months old, replace it and re-run the Drive Cycle. Even though your car may start just fine, the PCM or Power Train Control Module is hyper sensitive to the slightest glitch in the Battery and will suspend the Drive Cycle if it is not happy with any aspect of Battery Performance and/or Charging System performance."
My battery is 5 yrs old, so maybe there is something to it. Will try another battery tomm. If anyone has had the same probs., or any ideas, let me know.
The last 3 times I have tried to do the drive cycle, I have had it on jack stands. So much easier than parking at a spot, and letting it cool down, and being able to do 0-55mph for 5 mins. Not sure if having it jacked up is a good way to do it, but figured it couldn't hurt.