I have a 2001 Tracker V-6. In order to renew my registration in CA, I need to get it smogged. The smog check says "not ready." I use the Tracker as my RV toad, and the battery had been disconnected. Smog guy said to drive it 250 miles and then recheck. Did that, still "not ready." It appears to be the Oxygen Sensor component of the test (not sure if front or rear.) My check engine light has not come on, indicating a problem. Guy says to keep driving it and recheck. Any ideas?

Thx Rich Guess

 

Too bad you live in California, where smog control started. Not that I like smog, but it sounds like "smog-pump" which I absolutely hate. Disconnecting the battery means that the vehicle has to go through an entire system reset. Depending on vehicle it could take 50 miles or 200 miles but by 250 miles it should be done.If not something is wrong.

 

This is a tough one. The "smog check" is a series of I&M (Inspection & Maintenance) tests that run in the background.



The typical tests (above) vary from car to car.



Above are the I&M tests for a 2001 V6 Tracker. This screen shot from a GM Tech2 scanner only tells you if the test
was performed. It does not tell you if the test passed or failed. First find out which test is not running.



Even a generic OBD2 scanner will provide this information. The red dots indicate the valid Tracker tests.
N/A means this test does not apply to your car. OK means the test completed. INC means the test is
incomplete. The INC test will be the one you need to focus on.


Assume the O2 sensor test is not complete. There are 3 test conditions that must be met before
the test will run. There doesn't always have to be a problem with the O2 sensor for the I&M O2 test
not to complete. Remember, an incomplete test does not mean a failed test. And each I&M test
has its own set of test conditions that must be met before the test will run. That's why the inspector
told you to keep driving the car. But after 250 miles the test should have run.

The problem is there is vey little documentation on what to do if the test fails to complete.


Above is all the help you will get from Chevrolet. The text below is from a tech who has worked in the field.
his remarks mostly mirror what Chevy says.

"Mode 1 is where you will find the status of the onboard monitors. Each monitor is associated with a system or component on the car that can impact the emissions it produces. Monitors are classified as either continuous or non-continuous. The continuous monitors are the Comprehensive Component monitor, the Misfire monitor and the Fuel monitor. All the others are non-continuous.
Each monitor contains a test or series of tests the ECM uses to gauge the operational health of that system or component. The monitor status screen simply tells us whether all of the tests contained within that monitor have run to completion. When checked, they should all read Ready or Complete. If the vehicle you are testing does not use a given monitor, then the message will read Not Supported or Not Available.

Any monitor that reads Not Ready or Not Complete indicates a few things. Either the codes have been cleared with a scan tool, causing the monitors to reset, or battery power has been lost to the ECM. This can be a diagnostic aid. If power was lost due to a wiring fault or ailing battery, the ECM is constantly "rebooting" and this can cause some drivability issues. "

 

Looking at condition 1 of the 3 conditions required to run the O2 tests, one might assume if the temperature gauge in the
instrument panel is working then car has reached operating temperature. This can be misleading.


The temperature sensor on the V6 has two separate outputs. One drives the gauge in the instrument panel and the other feeds
the coolant data to the PCM. If the PCM gets bad info from the sensor it won't know what the engine temperature is.



The second condition looks at OPEN vs CLOSED loop. When the engine is cold the computer compares air data with
assumptions stored in memory to drive the fuel injectors. This is called OPEN (feedback) loop mode.


Once the O2 sensors come online the feedback loop closes and the PCM ignores the stored assumptions. The EPA wants the car running in CLOSED loop mode ASAP.



A generic scanner will tell you if the fuel system is in OPEN or CLOSED loop.



The third condition is battery voltage. Not the voltage at the battery but the battery voltage at the PCM. On a 2001 V6 that is pin 35 of connector C1. If the scanner provided a battery
voltage reading that will be the voltage at the PCM.