12-10-2012, 05:19 PM
Join Date: Jul 2007
Location: Show-me state
My Ride: 2001 BMW 330I
I have been following this thread with interest.
Originally Posted by jessehell
I realized that I misread my phone earlier as I was inspecting the SAP valve. The monitors that are not ready are Catalyst, O2 Heater, and Evap.
I just checked and the o2 heater fuse in the dme tray is not blown. Still no codes or SES light and I have about 700 miles on the car of me trying to set these monitors.
I really have no idea why the secondary air and o2 sensor monitors suddenly switched to ready after I had given up on drive cycles
Normally O2 sensor heater monitor is completed very early since it is monitored continuously in closed loop operation.
I am suspecting O2 sensors are not functioning properly. It appears that your O2 sensor system is borderline such that it will not set the fault code but not good enough to pass the test. If there is a wiring issue, a fault code will be set already. You may test it by disconnecting one sensor.
Catalytic convertor monitoring uses the signal from O2 sensors (all 4), and bad O2 sensor signals may explain why it is not set either.
You mentioned that you have Torque. If it is not a Torque Pro, please buy Torque Pro and log the following signals: engine rpm and all O2 sensor signals. Start logging 10 seconds before starting engine and stop two minutes after the secondary air pump stops. Here is how they should look like with new pre-cat O2 sensors. Post cat O2 sensors are less than 50K miles.
If you can't plot them, you can send me a CSV file.
Here is the EVAP system test criteria I wrote. There are more post about how I observed EVAP system monitoring in that thread.
Last edited by dslboomer; 12-10-2012 at 05:19 PM.