Toyota Emissions Readiness Procedure

It can be tricky to get your stock Toyota ECU to successfully run all of its emissions readiness tests after the ECU has been reset and this is usually required to pass your local emissions test. Here is the detailed information from Toyota on what the ECU is looking for in order to complete these tests. Monkeywrench Racing provides this information as a courtesy; unfortunately we’re not able to provide further tech support beyond the information listed below on this topic.

Toyota OBD Readiness Drive Cycles

EGR MONITOR DRIVE CYCLE

All models 1996-2002

Pre-Conditioning Requirements:
Altitude is below 7801 feet (2400 m).
IAT (Intake Air Temperature) must be above 13E F (-10E C).

Driving Procedure
If IAT is less than 50E F (10EC) at engine start-up, idle engine for 10 minutes.
Notes: Do not exceed 30% TPS. Maintain smooth throttle inputs, avoiding sudden accelerations.
Drive the vehicle at a steady speed between 43 & 56 mph (70-90 km/h) for three to five minutes.
Stop the vehicle and idle the engine for 3-5 minutes.
Repeat steps 1-3 once.
Notes: Readiness may not switch to complete if a pending code was set during the drive trace. Toyotas do report pending codes (using an enhanced scan tool). Pending codes are not considered a failure, and typically must be duplicated in order to set a DTC & MIL.

AIR/FUEL SENSOR HEATER MONITOR DRIVE CYCLE

All models 1996-2002

Pre-Conditioning Requirements:
Driving Procedure:
Start engine and allow it to idle for 9 minutes.
Drive the vehicle at 25 mph (40 km/h) or more for at least 2 minutes.

CATALYST (NON-A/F SENSOR) MONITOR DRIVE CYCLE

Certain Models 1996-2002

Pre-Conditioning Requirements:
ECT (Engine Coolant Temperature) must be 176E F (80E C) or more.
IAT (Intake Air Temperature) must be 14E F (-10E C) or more.
(2002 MY vehicles will run monitor at temperatures below 14E F by cycling key to OFF and repeating drive trace).

Driving Procedure:
Note the IAT data for use in step 3.
Drive the vehicle at a steady speed between 40-55 mph (64-88 km/h) or more for 7 minutes if IAT was below 50E F (10E C) at start-up, or 3 minutes if IAT was above 50E F (10E F) at start-up.
Drive the vehicle at 35-45 mph (56-72 km/h) for 7 minutes.
NOTES: Maintain smooth throttle inputs, avoiding sudden accelerations. Avoid sudden deceleration with closed throttle as much as possible.

CATALYST (A/F SENSOR) MONITOR DRIVE CYCLE

Certain Models 1998-2002

Pre-Conditioning Requirements:
ECT (Engine Coolant Temperature) must be 176E F (80E C) or more.
IAT (Intake Air Temperature) must be 14E F (-10E C) or more.
(2002 MY vehicles will run monitor at temperatures below 14E F by cycling key to OFF and repeating drive trace).

Driving Procedure:
Note the IAT data for use in step 3.
Drive the vehicle at a steady speed between 40-55 mph (64-88 km/h) or more for 7 minutes if IAT was below 50E F (10E C) at start-up, or 3 minutes if IAT was above 50E F (10E F) at start-up.
Drive the vehicle allowing speed to fluctuate between 35-45 mph (56-72 km/h) for 16 minutes.
Notes: Maintain smooth throttle inputs, avoiding sudden accelerations. Avoid sudden deceleration with closed throttle as much as possible.

EVAPORATIVE (VACUUM PRESSURE TYPE) MONITOR DRIVE CYCLE

Certain Models 2000-2002

Pre-Conditioning Requirements:
Fuel level is between 1/2 and 3/4 full.
(Preferred values- monitor may still run with tank fill between 15% and 85%).
Altitude is below 7801 feet (2400 m).
ECT & IAT is between 40 & 95E F (4.5-35E C).
Cold Soak Procedure is complete (see below).
(2002 MY vehicles will run monitor at temperatures below 14E F by cycling key to OFF and repeating drive trace).

IMPORTANT:
A cold soak must be performed prior to conducting the drive pattern in order to complete the Internal Pressure Readiness Monitor (see below).

Cold Soak Procedure:
Let the vehicle sit 8 hours, or until the difference between IATand ECT is less than 13E F (7E C).

Driving Procedure:
Release pressure in the fuel tank by removing and re-installing fuel cap.
Start the engine and allow it to idle until ECT is 167E F (75E C) or more.
Raise the engine speed to 3,000 RPM for ten (10) seconds.
Idle engine with the A/C on (for additional load) for 15-50 minutes.
(If no A/C, set parking brake and chock wheels. Once immobilized, idle vehicle in drive).

EVAPORATIVE (WITH NO LEAK DETECTION) MONITOR DRIVE CYCLE

Certain Models 1996-2000

Pre-Conditioning Requirements:
Altitude is below 7801 feet (2400 m). ECT is 181E F (83E C) or more.
IAT is 41E F (5E C) or more.
Driving Procedure: (this is the same driving trace used by the EGR monitor).
Drive the vehicle at a steady speed between 43 & 56 mph (70-90 km/h) for three to five minutes.
Notes: Do not exceed 30% TPS. Maintain smooth throttle inputs, avoiding sudden accelerations.
Stop the vehicle and idle the engine for 3-5 minutes.
Repeat steps 1-3 once.

OXYGEN SENSOR MONITOR DRIVE CYCLE

Certain models 1996-2002

Pre-Conditioning Requirements:
Driving Procedure:
Drive the vehicle at a steady speed at or above 25 mph (40 km/h) for at least 50 seconds. Maintain engine speed above 900 rpm.
Stop the vehicle and allow the engine to idle for 40 seconds or more.
Repeat steps 2 & 3 nine (9) more times.

AIR-FUEL RATIO (OXYGEN) SENSOR MONITOR DRIVE CYCLE

Certain models 1998-2002

Pre-Conditioning Requirements:
Driving Procedure:
Start the engine and allow it to idle 2 minutes.
Drive the vehicle at a steady speed between 40-70 mph (64-112 km/h) or more for 3 minutes. Maintain engine speed between 900 & 3,200 rpm.
Stop the vehicle and allow it to idle for ten (10) seconds or more.
Drive the vehicle at a steady speed above 25 mph (40 km/h) or more for at least 40 seconds. Maintain engine speed above 900 rpm.
Stop the vehicle and allow it to idle for ten (10) seconds or more.
Repeat steps 5 & 6 nine (9) more times.