96 E320 OBD II non-continuous monitors
 

Hi All,
I am new to this so pls bear with me. My 96 E320 failed the CA smog test due to "not ready" status for Catalyst, Evaporative Sys, Sec Air Sys, O2 sensor, O2 sensor heater and EGR system dispite passing the emission portion of the test. Is the problem with the Diagnostic Module or the ECU. Your help will be greatly appreciated. Many thanks.

On 1996 model cars, OBD2 readiness is a tough issue.

For the car to get "ready" after a check engine light OR battery disconnection, the front O2 sensor must be PERFECT.

Of course it's not how far you drive, BUT how you drive.
You must drive slow w/o load.

The diagnostic module is the problem.

Thanks MBDoc! I have just purchased a used diagnostic module. Question is - do I have to go thru the drive cycle after I replace the module to achieve the ready status for OBD II? The prescribed E320 drive cycle is pretty complex. I am trying to figure out how to complete that without getting into an accident!

Yes, any time the battery is disconnected, codes erased, OR in your case the computer is removed you will have to perform a drive cycle to have the sensors get ready.

I completed the drive cycle but only got 3 out of the 6 monitors in a ready state. Looks like I will have to redo the drive cycles again. I just need one more to squeak past on the smog test! At what point do I have to start replacing parts such as the O2 sensors or EGR valve? The OBD II scanner does not return any codes and there are no stored faults. :confused:

Thanks for the pointers!!!!