After resetting your obd how many miles do you have to drive your 1998 Isuzu Rodeo before it will be obd ready for an emissions test?

Answer 1

There is not a fixed mileage associated with resetting the test monitors as it's really based on cycles. Normally though, 4 or 5 different trips and at least 400 miles are usually required. There is an inexpensive "ready or not" test device available that will tell you instantly when the monitors have reset

OBD-II Ready-or-Notâ„¢ Test Tool

http://tunertools.com/proddetail.asp?prod=ST-430100

I recently did this after repairing my rodeo and drove with the scan tool connected to see how quiickly it would be ready, In Nevada you can have 2 unsets ( 2 monitors not ready ) and still pass emissions, after 5 miles I had 5 of 8 monitors ready, another 10 miles and I had 6 of 8. This equalled about 30 minutes of driving, the other 2 monitors took another 30 minutes to be ready.

Drive Cycle: The 1998 Izusu Rodeo uses the GM early model catalyst cycle, late model evap cycle, GM egr and o2 sensor cycles. There is no drive trace as a whole, however, some monitor cycles are similar and may pass through simultaneously Catalyst moniotor: Pre-req: no codes present, IAT above 32 deg f; ECT is above 167 deg f; mass air flow greater than 15 gm/s, engine load is below 63% and steady, engine speed is below 3000 rpm -Idle vehicle 5 minutes until it is in closed loop -drive 5 min at steady speed above 50 mph -drive 2 min at steady 40 mph -drive 2 min at steady 50 mph EGR Monitor: Pre-req: no codes present, ECT is avove 75 deg f; barometric pressure above 72kPa 1. Idle vehicle 5 minutes until it is in closed loop 2. Accelerate and drive for 1 min at steady speed above 50 mph 3. coast vehicle down to 20 mph (vehicle in drive or w/ clutch engaged, brake off) 4. repeat steps 2 and 3 four times * the GM egr runs during the deceleration portion of the drive trace Evaporative Monitor: Pre-req: no codes present -drive 5 min at steady speed between 30 and 40 mph -stop and idle 2 min O2 Sensor Monitor: Pre-req: no codes present, IAT above 32 deg f; ECT is avove 167 deg f -Idle vehicle 5 minutes until it is in closed loop -drive 3 min at steady speed above 50 mph -drive 2 min at steady 40 mph -drive 2 min at steady 50 mph