OBD_II Emissions Readiness Test (Long)

Lewis Shadoff lshadoff@brazosport.cc.tx.us
Fri, 10 Oct 2003 11:07:24 -0500


I recently got my car running after working on it, off and on, for over a
year.  I drove directly to the emissions test station and failed the
Readiness Test (Catalyst, O2 Sensor, and EGR System not ready).  I was told
that removing the battery or resetting the MIL codes, resets the Readiness
and to drive around and they would set themselves.  The second day I got a
ticket for an expired inspection sticker.  I went to court and explained
all the stuff below to the judge, before I got a new inspection sticker,
and he waived the fine.

I went back to the test station three more times (15 day grace period)
and  the same three sensors were not ready.  I started looking up
information about the readiness test on the Internet and found some
interesting stuff:

The 1996 & 1997 200SX SE-R is noted as being particularly difficult to set
the  EVAP and catalytic converter.
(1) http://www.babcox.com/editorial/us/us50326.htm
(2) http://www.dmvstat.com/pdfforms/ecnews1st03.pdf

There is a Drive Pattern which will set the monitors, but it varies from
one vehicle to another. See (1) above.

I found that there is a Nissan Technical Service Bulletin 98-018C which
contains the drive patterns for certain vehicles including the 200SX SE-R
and the Sentra/200SX GA18.  I joined AllData (http://www.alldata.com/) and
downloaded the drive patterns for the 200SX SE-R.  It works, but you must
follow the directions EXACTLY.  That means starting with a cold car and
driving as instructed.  I only needed to have less than three monitors set,
so I started with a cold car, drove to a nearby expressway, and started
with #4.  It set the 02 Sensor and Catalyst in one pass!

Here are the instructions:

200SX SE-R Auto Trans
1.  Engine coolant less than 158:.  Start and idle 1.5 min.
2.  RPM 1300-1500, D(OD ON), AC ON, constant load*, 3 min.
3.  THEN 50-70mph, 1800-2000rpm, D(OD ON), constant load*, 1.5 min.
4.  Idle for 10 min., then switch off, then restart
5.  IMMEDIATELY Cruise Control 50-60mph, D(OD OFF), >3000rpm, no
deceleration**, 3 min.
6.  THEN Cruise Control 53-58mph, D(OD ON), 2100-2500rpm, AC ON, no
deceleration**, 3 min.
7.  D(OD OFF), decelerate no gas at least 5 seconds, then idle 1min in park

* I assumed it is constant load, but the instructions say "B/F SCHDL
2.3-2.5 msec" for #2 and "2.0-3.5 msec" for #3.
**No deceleration for more than 3 sec. or you must start over with a cool
car.

200SX SE-R Manual Trans
1.  Engine coolant less than 158:.  Start and idle 1.5 min.
2.  RPM 1800-2200,  AC ON, constant load*, 3 min.
3.  THEN 50-59mph, 2000-2800rpm,  constant load*, 1.5 min.
4.  Idle for at least 10 min., then switch off, then restart
5.  IMMEDIATELY 50-60mph, 4-th Gear, >3000rpm, 3 min.
6.  THEN Steady State Cruise 53-58mph, 5-th Gear, 2500-2700rpm, no
deceleration**, AC ON
7.  Downshift, decelerate no gas at least 5 seconds, then idle 1 min. in
neutral

* I assumed it is constant load, but the instructions say "B/F SCHDL
1.5-1.7 msec" for #2 and "2.0-3.0 msec" for #3.
** No deceleration for more than 3 sec. or you must start over with a cool
car.

1,2, &3  O2 Sensor Heater and EGR
4 through 7  CATALYST and O2 Sensor

The car does not give any visual indication about the Readiness Test, so I
used my EASE Diagnostics OBD-II program for my laptop computer.  It plugs
into the OBD-II port under the dash and reads out, among other things, the
Readiness status.  I drove through the drive pattern  with it connected,
and could see whether the sensors were set.

On my car, when the engine is turned off and turned back on, those three
sensors read Not Ready, and I had to go through the pattern, drive directly
to the test station, and leave the car running through the entire emissions
test.

That new inspection sticker sure looks good!

Lew

Lewis Shadoff
Lake Jackson, TX
'97 200SX SE-R, Level 10 Auto, HotShot turbo
http://www.brazosport.edu/~lshadoff/turbo/

Lewis A. Shadoff, Ph.D.
Brazosport College
Lake Jackson, TX