We replaced an injector to correct a misfire issue.The vehicle had failed inspection with 2 codes present(PO174 & PO308).We replaced a spark plug & an injector.When the vehicle originally went to inspection readiness monitors were ok but codes were present. We performed our repair, the vehicle was used for a few days(run at various speeds),taken back to inspection and turned down for monitors not ready. Any insights?
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2001 Ford F-150 Question: How long does it take for readiness monitors to reset?
Answer #1lightsaber July 30, 2013, 10:14Technician
The ford drive cycle is fairly lengthly, but the following routine should set all monitors in one - three sessions. Gas tank should be around half full, and do this in the morning before outside temperature gets too warm. avoid quick acceleration, sharp turns, fast braking, etc that would slosh the fuel in tank. plan your route ahead of time. The engine cannot be turned off during test. start engine and idle for one minute turn air conditioner on for 1 minute apply brake and slowly shift through all gears ending in park (20 seconds) drive at 15 mph for 1/4th mile accelerate smoothly to posted residential speed for 1/2 mile access a highway and drive 45 mph for 1 mile remove your foot from gas pedal and coast to around 5 mph and pull over put transmission in park and wait one minute shift back to drive, enter roadway, and accelerate at one third throttle until posted speed is acquired drive for one mile then slow down to 30 mph below posted speed accelerate at 3/4 throttle to posted speed and drive at posted speed for a couple miles drive in city stop and go traffic for ten miles the engine should by now be at operating temp go home and park the vehicle overnight The monitors might set in one drive cycle, but usually take two. Go to an Autozone parts store to have the monitors checked for free to verify they have run and completed
ReplyLonesome Dave, July 31, 2013, 06:23Rookie
Thanks for your input.This vehicle is used by our shift workers(24 hour crew) and our repair was performed about 2 weeks ago. Why is this process so hard to effect?Read your own reset formula... who on Earth drives like that!?! I've driven this vehicle abot 50 miles,let it cool,let it warm up just about every real life scenario I can think of.Our Operations crew has used it for a few weeks...good Lord.No codes,no CEL vehicle runs appropriately but I can't get it through inspection because of some bogus readiness monitor failing to reset. Seems like this is way too hard! I read there may be a software glitch solved by reflashing the PCM. Yes/no? I'm getting antsy with this situation.Any more input would be appreciated.
Replylightsaber, July 31, 2013, 08:30Technician
For the drive cycle to work,the engine temperature must increase at least 40 degrees during the drive cycle, and it is better if run from a cold start and ending at full operating temperature.
The monitors are initiated for testing by the "executive director" in the pcm in a set order. One at a time. If one monitor cannot set due to whatever mechanical issue hinders it, the remaining monitors won't even have the chance to run, ever. The misfire monitor should set quickly upon startup. the evap leak tests require the tank to be 1/2 full, and slow initial driving to check for leaks. The cat monitor sometimes takes two drive cycles to set, etc.
The monitors for the OBD11 system are there to please the government and ensure that our vehicles do not polute the air. When you go to get an emissions sticker for your vehicle, the monitors are showing the government that your vehicle is not poluting.
The above drive cycle should take no more than one hour to perform. If all is well with the mechanicals, all the monitors should be set except for maybe the cat, but it should be set after a longer drive without the drive cycle. So have one of your employees do the drive cycle, and then go about their daily duties with the vehicle. After a couple of normal business days have your mechanic check the monitors to see if they have all run, and set! If they have not all set, you need to look for the reason. You should also know that the above drive cycle works but is a chopped version of the much longer Ford drive cycle.
Furthermore, each time the battery is disconnected for replacement,etc, or the error codes are erased after a repair, the monitors will need to be re-set as they are also cleared.