LarryK557

I am trying to find out if anyone knows how to clear not ready codes for a 1996 993, not ready codes are as follows. Catalyst, Evap, Secondary Air, O2 Sensor, O2 Heater. The Catalytic Converter: Pass The V Smoke/ Emissions: Pass The V Gas Cap: Pass. The vehicle has been driven these codes haven't reset> Any Ideas, Please Help.

goofballdeluxe

Try a search; this subject has been already been discussed many many times. Archives and old threads should answer most/all your questions

Slow Guy

Search on "OBDii Readiness Indicators", as Goofball said we've got many threads on this subject.

Jeff U

Try this:

• Start engine, let idle for approx. 2 min, 10 secs.
  
• Accelerate to 20-30 MPH, Maintain steady speed for approx 3 min, 15 secs.
  
• Accelerate to 40-60 MPH, Maintain steady speed for approx 15 mins.
  
• Decelerate and come to a stop. Then:
  
• Idle in Neutral for 5 mins. (manual trans.)

During the drive cycle, do not exceed 3,000 rpm or 60 mph.

You may have to do this a couple times but it will work. Or, least it did for me.