Originally Posted by fordtech
even if you have cleaned the MAF sensor clean it again. Spray it with some cleaner and clean it CAREFULLY with a cuetip .But before you do this unplug the battery for at least an hour and then put it all together and wait another ten mins and then plug in the battery and turn it on this code has to do with the MAF sensor since alll you did was change out the filter this is the only thing that could be wrong also clean out the sensor plug with electric parts cleaner.
And it does take 20 miles for all the systems on the vehicle to run their first cycle I've had cars that ran fine for 20 miles and then throw a code this is after all the engine management systems are fully in sync that why a car will run fine right after you first hook on the battery even though its throwing codes after a while.
Originally Posted by djfllmn
well the ECM in our trucks are two trip systems...that means it will throw a code if it sees a problem for 2 consecutive trips
there are some systems that require the vehicle to complete one, two or numerous drive cycles for the CEL to illuminate, not just two trips in the vehicle, but two drive cycles of the PCM...there are some systems like MAF that are constant monitor systems, as soon as you unplug the MAF the CEL will go on...fodtech, i hope you dont work at a dealership, thats one of the first things you are taught in ford training is what has to happen to complete an OBDII drive cycle
Description of On Board Diagnostic (OBD) Drive Cycle
The following procedure is designed to execute and complete the OBD monitors and to clear the Ford P1000, inspection/maintenance (I/M) readiness code. To complete a specific monitor for repair verification, follow steps 1 through 4, then continue with the step described by the appropriate monitor found under the OBD Monitor Exercised column. For the EVAP/secondary AIR monitor to run, the ambient air temperature must be between 4.4 to 37.8°C (40 to 100°F), and the altitude below 2,438 meters (8,000 feet). If the P1000 code must be cleared in these conditions, the powertrain control module (PCM) must detect them once (twice on some applications) before the EVAP monitor can be bypassed and diagnostic trouble code (DTC) P1000 is cleared. The EVAP bypassing procedure is described in the following drive cycle.
The OBD drive cycle is carried out using a scan tool. Refer to the manufacturer's instruction manual for each described function.
A detailed description for clearing the DTCs is found in this section. Refer to Clear The Continuous Diagnostic Trouble Codes (DTCs) And Reset The Emission Monitors Information in The Powertrain Control Module (PCM).
Drive Cycle Recommendations
WARNING Strict observance of posted speed limits and attention to driving conditions are mandatory when proceeding through the following drive cycles. Failure to follow these instructions may result in personal injury.
1. Most OBD monitors complete more readily using a steady foot driving style during cruise or acceleration modes. Operating the throttle in a smooth fashion minimizes the time required for monitor completion.
2. The fuel tank level should be between 1/2 and 3/4 full with 3/4 full being the most desirable.
3. The evaporative monitor can operate only during the first 30 minutes of engine operation. When executing the procedure for this monitor, stay in part throttle mode and drive in a smooth fashion to minimize fuel slosh.
4. When bypassing the EVAP engine soak times, the PCM must remain powered (ignition ON) after clearing the continuous DTCs and relearning emission diagnostic information.
For best results, follow each of the following steps as accurately as possible:
OBD Monitor Exercised Drive Cycle Procedure Purpose of Drive Cycle Procedure
Drive Cycle Preparation Note To bypass the EVAP soak timer (normally 6 hours), the PCM must remain powered after clearing the continuous DTCs and resetting the emission monitors information in the PCM.
1. Install the scan tool. Turn the ignition on with the engine off. Cycle the ignition off, then on. If needed, select the appropriate vehicle and engine qualifier. Clear the continuous DTCs and reset the emission monitors information in the PCM. Bypasses the engine soak timer. Resets the OBD monitor status.
2. Begin to monitor the following PIDs (if available): ECT, EVAPDC, FLI and TP MODE. Start the vehicle without returning the ignition to the OFF position.
3. Idle the vehicle for 15 seconds. Drive at 64 km/h (40 mph) until the engine coolant temperature (ECT) is at least 76.7°C (170°F). Executes SEC AIR flow check monitor (if applicable).
Prep for Monitor Entry
4. Is the intake air temperature (IAT) between 4.4 to 37.8°C (40 to 100°F)? If not, complete the following steps, but note that step 14 is required to bypass the EVAP/secondary AIR monitor and clear DTC P1000. Engine warm-up and provides IAT input to the PCM.
5. Cruise at 64 km/h (40 mph) for at least 5 minutes. Executes the HO2S monitor.
6. Cruise at 64 to 89 km/h (40 to 55 mph) for 10 minutes (avoid sharp turns and hills). NOTE: To initiate the monitor, the throttle should be at part throttle, EVAPDC must be greater than 75%, and FLI must be between 15 and 85%, and for fuel tanks over 25 gallons FLI must be between 30 and 85%. Executes the EVAP monitor if the IAT is between 4.4 to 37.8°C (40 to 100°F).
7. Drive in stop and go traffic conditions. Include 5 different constant cruise speeds, ranging from 32 to 89 km/h (20 to 55 mph) over a 10 minute period. Executes the catalyst monitor.
8. From a stop, accelerate to 72 km/h (45 mph) at 1/2 to 3/4 throttle. Repeat 3 times. Executes the EGR monitor.
SEC AIR/CCM (Engine)
9. Bring the vehicle to a stop. Idle with the transmission in drive (neutral for M/T) for 2 minutes. Executes the idle air control (IAC) portion of the comprehensive component monitor (CCM) and the SEC AIR functional check (if applicable).
10. For M/T, accelerate from 0 to 81 km/h (0 to 50 mph), and continue to step 12. For A/T, from a stop and in overdrive, moderately accelerate to 81 km/h (50 mph) and cruise for at least 15 seconds. Stop the vehicle and repeat without overdrive to 64 km/h (40 mph) cruising for at least 30 seconds. While at 64 km/h (40 mph), activate the overdrive, accelerate to 81 km/h (50 mph) and cruise for at least 15 seconds. Stop for at least 20 seconds and repeat step 10 five times. Executes the transmission portion of the CCM.
Misfire and Fuel Monitors
11. From a stop, accelerate to 97 km/h (60 mph). Decelerate at closed throttle to 64 km/h (40 mph) (no brakes). Repeat this 3 times. Allows learning for the misfire monitor.
12. Access the On-Board System Readiness (OBD monitor status) function on the scan tool. Determine whether all non-continuous monitors have completed. If not, go to step
13. Determines if any monitor has not completed.
Pending Code Check and EVAP Monitor Bypass Check 13. With the scan tool, check for pending codes. Conduct the normal repair procedures for any pending code concern. Otherwise, repeat any incomplete monitor. If the EVAP monitor or SEC AIR monitor is not complete and the IAT was out of the 4.4 to 37.8°C (40 to 100°F) temperature range in step 4, or the altitude is over 2438 m (8000 ft.), the EVAP bypass procedure must be followed. Go to Step 14. Determines if a pending code is preventing the clearing of DTC P1000.
EVAP Monitor Bypass
14. Park the vehicle for a minimum of 8 hours. Repeat steps 2 through 11. Do not repeat step 1. Allows the bypass counter to increment to 2.