OK, so we were successful to get all the monitors set in a little less that 60 miles of driving - and I'm pretty convinced that we can potentially do a little better (fewer miles) next time. Please note that the following advice/recommendations are intended to those owners who need to complete a CA SMOG check AND who have recently either 1) replaced their battery, or; 2) have used a scan tool recently to reset a CEL. Either of these will reset the ECU monitors in the GT and unfortunately, the monitors must be complete in order for you to pass a smog check.
If your battery is weak but not completely dead, your monitors may still be OK. Check them first because you can bypass this whole crappy process if your monitors have not been cleared. If possible, get your SMOG test before you replace the battery. If you need to change your battery first, use the GT's cigarette lighter to input 12v from an independent source while you change the battery. This will keep the ECU powered throughout the battery change process and you won't have to worry about the monitors - they'll remain set.
Anyway, if you're in the situation where the monitors have to be reset, here's my recommendations for doing it;
1. You will need to purchase and attach a "code reader" that will give you the status of the ECU's monitors. (I like the Autel AL519 because at $79 it is inexpensive and easy to use.) For the Autel and most other scanners the status of the monitors is NOT dynamic. You need to command the Autel to check the monitors (while you are driving or stopped at a traffic light, for example.) Once you observe the status of the monitors, you need to ESCape out of that mode and then be ready to query the monitor status again later on. If you leave the monitor status screen up, it will not update as the monitors are cleared.
2. If your car has an alternate program loaded into it, it is probably best to re-load the OEM software while you attempt to get the monitors to set. (Note that if you have the Ford Racing pulley/tune, you can LEAVE it installed.) Also, if you have a MAF scaler such as a MAFIA, you need to remove or bypass it so that your ECU gets an un-altered MAF count signal. You will be safe driving your car like this - with a smaller pulley but with the OEM ECU program, but DON'T use boost. Just drive moderately and avoid mid to high throttle levels and you'll be fine.
3. One final step before getting started here. Fill your gas tank such that you are between 3/4 and full. 7/8 is ideal, but don't worry too much if you fill it all the way up.
4. Start and drive the car normally. Take a cruise on the freeway and try to stay at a constant speed less than 65mph. No hills and no sharp turns. (We are trying to get EVAP to reset with this process and we don't want the fuel to slosh around.) After 10 or more minutes, exit the freeway and get yourself into city traffic. When it is safe, use the SCAN tool to check the monitors. Most monitors will set rather quickly although EVAP and CATalyst typically are most troublesome. As I mentioned in a previous post, EVAP needs an outside temperature differential to perform its test and in my experience, this always involves an overnight "sit" before resuming the test. My advice is to focus on the CATalyst monitor and with any luck the EVAP may reset too. (No worries if it doesn't.)
Keep driving in stop and go traffic. Purposely TRY to miss traffic lights. Accelerate moderately at a green light and try to miss the next light - and let the car slow to a stop while in gear. Downshifting is ok - just let the engine/trans slow the car and come to a complete stop. Keep doing this. Between lights, target DIFFERENT cruise speeds between lights - between 25 and 45. Stop and take a break, and check the monitor status. If CATalyst is not set, keep doing this city driving. Moderate acceleration (avoid boost), cruise between 25 and 45 - choose different speeds between lights, and TRY to miss lights so you can decel with engine and come to a stop.
5. OK, good news bad news here. Good news: CA will accept 1 monitor not being reset. Bad news: The ONLY monitor exception is EVAP. So, if you get all the monitors reset except for EVAP on day 1, you can proceed to the SMOG station. If you want them all reset, give the testing a break overnight and resume the next day. The EVAP will likely set pretty quickly and, if needed, you can focus on the stop & go needed to get the CATalyst monitor to reset.
Best of lust. Not super easy, but not all that hard, either.
