Replacing the battery or even having simply disconnected the battery on your Dodge Durango causes the engine control unit (ECU) to reset and subsequently clear all the emission monitors (and trouble codes; if any existed). Your Durango's engine control unit performs internal self-tests in order to ensure the engine is running efficiently and not polluting. These self-tests are called Monitors. The entire process of self-testing various emission control systems is called a Drive Cycle.
You mention having already driven hundreds of miles, trying to get the emission monitors to reset, but without success. Typically driving 200-300 miles through various traffic conditions and over the course of a few days is enough to get the drive cycle to initiate; and readiness monitors to become READY or COMPLETE. At times however simply driving an extend length of time does not make the monitors complete.
We're going to recommend following the Dodge Durango drive cycle indicated below. It should get the catalyst monitor, as well as the EGR, EVAP and AIR monitors, ready for the smog inspection.
Notice: Obey all traffic laws while performing drive cycles. Perform the drive cycle cautiously and at your own risk. Use a OBD-II scan tool to check the status of the monitors once you've completed the drive cycle at least once.
How To Perform Dodge Durango Drive Cycle
A. All Monitor Drive Trace - This will complete all emission monitors without having to perform specific monitor driving patterns.
Pre-Conditioning Requirements:
MIL must be off - Cold start (Cold soak required; vehicle must be sitting overnight, at least 8 hours). Fuel level is between 15% and 85%. Make sure your gas tank never has a full tank nor less than 1/4 of fuel during the drive cycle.
Driving Procedure:
1) Warm engine up for five minutes (must reach closed loop)
2) Drive (with steady throttle) at a speed between 40 and 60 mph for 8 minutes.
3) Stop and idle for 3 minutes.
4) Drive (with steady throttle) at a speed above 20 mph for 2 minutes.
5) Turn key off, leave off for ten minutes (to run O2 sensor heater monitor).
B. Catalyst Monitor Drive Trace
Pre-Conditioning Requirements:
- MIL must be off.
- No DTCs present.
- Fuel level is between 15% and 85% full.
- ECT above 70º F.
- Engine must have run at least 90 seconds
- Engine between 1,350 & 1,900 rpm.
Driving Procedure:
1) Idle vehicle for five minutes (to reach closed loop operation).
2) Drive with a steady vehicle speed between 30 and 45 mph for 2 minutes.
C. EGR System Monitor Drive Trace - Vacuum controlled
Pre-Conditioning Requirements:
- MIL must be off.
Driving Procedure:
1) Idle vehicle for five minutes (to reach closed loop operation).
2) Drive with a steady vehicle speed between 40 & 60 mph for 8 minutes.
D. EGR System Monitor Drive Trace - Electronic
Pre-Conditioning Requirements:
- MIL must be off.
- MAP must be between 0-60 KPa.
- Engine speed between 500-850 rpm.
- ECT is above 180º F (90º C).
- No misfire temporary (pending) or matured fault present.
- A/C clutch, PS Switch and Cooling fans do not change state (turn off).
Driving Procedure:
1) Idle vehicle for five (5) minutes (to reach closed loop operation).
2) Drive with a steady vehicle speed between 40 & 60 mph for 2 minutes.
3) Idle vehicle for three (3) minutes.
E. Evaporative System Monitor Drive Trace
Trace 1: Standard Type
Pre-Conditioning Requirements:
- MIL must be off.
- No Evaporative DTCs present.
- Fuel level is between ½ and full.
(Note: monitor may still run with tank fill between 15% and 85%).
Driving Procedure:
1) Idle vehicle for five minutes (to reach closed loop operation).
2) Drive with a steady vehicle speed between 30 and 45 mph for 2 minutes.
Trace 2: Leak Detection Pump
Pre-Conditioning Requirements:
- MIL must be off.
- No Evaporative DTCs present.
- Fuel level is between 30 & 85 % full.
Driving Procedure:
1) Cold soak vehicle, start and idle vehicle for 4 minutes.
2) Drive in-town (stop and go) for 5 minutes, using smooth accelerations and decelerations.
3) Stop and idle vehicle for 4 minutes.
F. O2 Sensor Monitor Drive Trace
Pre-Conditioning Requirements:
- MIL must be off.
Driving Procedure:
1) Idle vehicle for five minutes (to reach closed loop operation).
2) Drive with a steady vehicle speed above 25 mph for 2 minutes.
3) Stop and idle for 30 seconds.
4) Smoothly accelerate to a speed between 30 and 40 mph.
5) Repeat steps 3 & 4 five (5) times.
G. O2 Sensor Heater Monitor Drive Trace
Pre-Conditioning Requirements:
- MIL must be off.
Driving Procedure:
1) Idle vehicle for five minutes (to reach closed loop operation).
2) Shut engine off and leave vehicle off for ten minutes.
