Long time reader, first time poster. I purchased my first MBZ, a 96 E320 with 207k. Ive read alot of the posts on here about drive cycles and reset procedures. I fixed a "secondary air inj" code, and ever since I cannot get these set:
Catalyst Monitor INC
O2 Sensor Mon INC
O2 Heater Mon INC
Ive read on these pages that the Cat Mon wont reset unless it reads the rear O2 sensor. Never have I had a code for O2 sensors, nor do I know the last time they were changed if ever.
Im dying to get this tagged, so I can shake it down.
HELP!

 

I found that 3 drive cycles (start cold, warmup, and drive at atleast 45mph for 20 min) over a couple of days reset everything. There are specific MB procedures of the minimum necessary.

Of course, that assumes there are no issues that would cause a code.

 

you are over 100K miles in excess of the replacement interval for the o2 sensors.
Replace the old tired ones gain back the lost mpg and ready the I/M monitors.
How long have you been driving it since the repair? And did you erase the sec air code or let it clear on its own?

 

I did infact change out both O2 sensors yesterday 4/17, and replaced a vac. hose on the secondary air inj. back on the 4/2. I didnt just "erase and run". Ive not had any code come back in over 300 miles of combined street/freeway driving after 4/2. I took the wife the long way to Sams Club, doing a drive cycle at the same time, when I coasted down to 20mph and went to the side of the road she thought something broke!

 

OK, So the O2 monitor and O2 heater readiness are set now but the Catylist monitor still has not. Ive got two more days on my temp tag.......heres to hope.

 

Check your local laws. You may be allowed to have 2 systems in Not Ready status.

 

almost every state allows at least one if not two not ready I/M monitors.
(Except on new cars that are exempt or required by the state to have the dealer fix emissions problem under new car warranty.)
Especially on older cars. You should pass with no problem.
Be sure you are warmed up before the test,don't do it on a cold engine.

 

YES...It passed with only one not set. Thanks for the input folks. Now off to work out the A/C only cold out the right side. Ive got the procedure for pulling those codes.

 

Hello, All
Thanks especially to OhLord for his many posts here and on BenzWorld.org on Drive Cycles, IM Readiness and other useful stuff.

In order to smog test, all IM Readiness monitors must now be set.

Ref.
§ 3340.42.2. Test Methods and Standards for the*On–Board Diagnostic inspection*
C.Starting on or after January 1, 2013, OBD*equipped vehicles shall fail the OBD inspection if any*one of the following conditions occurs as applicable to the*vehicle:*
(9) The vehicle’s OBD system reports incomplete*readiness monitor(s) as specified below:*
(B) Gasoline-powered vehicles model-years 2000*and newer with any incomplete monitors, excluding the*evaporative system monitor;*

(Implementation date was set for March 9, 2015)

At least it helps to know the changing rules.