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Brad B
Brad B, Ford Technician
Category: Ford
Satisfied Customers: 1091
Experience:  ASE Master Certified & ASE G1. Ford Senior Master
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Why catalytic converter read not ready

Resolved Question:

why catalytic converter read not ready
Submitted: 7 years ago.
Category: Ford
Expert:  Bamaman39 replied 7 years ago.

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I need a little more information what do you mean by catalytic not working yet?

Customer: replied 7 years ago.
we have it replaced by new one and every time we go to the emission test the computer says that the part is fixed but not ready....they recommended to us that we have to drive it a lot but after 2000 mil we still have the same problem
Expert:  Bamaman39 replied 7 years ago.

Did you replace the convertor or the oxygen sensors?


Im trying to understand what you mean by not ready. Once you put a convertor on its ready for use

Who is doing the scan?.

Edited by Bamaman39 on 5/30/2010 at 3:32 PM EST
Customer: replied 7 years ago.
The scan is done by technician at the emission test facility..
Expert:  Brad B replied 7 years ago.



New technician here. The catalytic converter does not need to have anything done to it to aid in emissions compliance. As stated by the other technician once the catalytic converter is installed it is ready to work. The oxygen sensors monitor the catalytic converter and if their is a problem the computer will set a code saying their is an issue. If the catalytic converter is not working correctly the oxygen sensor will set a code or if the vehicle is getting too much or not enough fuel the computer will also set a code. If the computer says that the oxygen sensors are not ready this is due to the vehicle not being warm enough which it generally only takes 2 - 5 minutes for the exhaust to be fully warm up for the system to read.


Is the vehicle sitting for some time before the test is done? If so you need to make sure the exhaust is warm before the test. The emissions shop should know this though when they do the test. Have they told you anything to what the problem may be for this concern, other then just driving the vehicle? I would highly suspect the issue is just from the exhaust not being warmed up enough (unless you have a check engine light then the oxygen sensor may be the cause).


If the check engine light is not on then the system should be working correctly. Also the emissions shop should be able to monitor the oxygen sensor to see if it is reading the fuel trim of the vehicle.


If the coolant temperature gauge of the vehicle is reading lower than normal this may be causing the issue as the system is not seeing the system fully warm.


If you have any questions please let me know!

Brad B, Ford Technician
Category: Ford
Satisfied Customers: 1091
Experience: ASE Master Certified & ASE G1. Ford Senior Master
Brad B and 3 other Ford Specialists are ready to help you
Customer: replied 7 years ago.
oxygen sensor is new, the car is always hot not just warm and the computer doesn't show any codes...they didn't recommended anything else except more driving.. so what is your answer to this problem?
Expert:  Brad B replied 7 years ago.

Being you have no apparent issues with the vehicle the issue can be from having a code P1000 in the system, this is a code that is set when the vehicle has not been through a complete drive cycle. Depending on how you are driving the vehicle you may not be allowing the vehicle to be put into the proper drive cycle. I have attached some information for you to read over on a drive cycle to better understand the issue;


Test Notes

Enter this pinpoint test only when directed here.

NOTE: It is not necessary to clear DTC P1000 from the PCM by driving the vehicle unless it is requested by the customer to pass an inspection/ maintenance test. Inform the customer of the need for additional driving when required to pass an inspection/maintenance test.

Diagnostic Trouble Code (DTC) P1000 indicates that not all of the On Board Diagnostic II (OBD II) monitors have completed. In some states, this DTC must be cleared to pass an inspection/maintenance test. The customer should be informed that the law specifies additional city and highway driving must be done to complete the check of the on board diagnostic system. This additional driving must occur before the vehicle is tested at the inspection/maintenance station. The amount of driving required varies with individual driving patterns.

NOTE: The only way a DTC P1000 can be removed from memory is when all the OBD II monitors have successfully completed.

DTC P1000 is set by the PCM with any of the following conditions:

- The vehicle is new from the factory and has not yet completed an OBD II drive cycle.
- The battery or PCM has been disconnected.
- An OBD II monitor failure had occurred before completion of an OBD II drive cycle.
- The PCM DTCs have been cleared with a scan tool as part of a service process.

DTC P1000 cannot be cleared from the PCM when:

- If the vehicle has a Power Take Off (PTO) , the circuit is shorted to VPWR or B+, or the PTO is ON during testing.


Here is a link that may help you;'drive_cycle'


The Ford method to perform a drive cycle for your vehicle is to drive the vehicle when the air intake temperature is between 50 and 100 degrees (being it is not winter you will have no worries with the temperature issue of the air intake sensor) and when the fuel tank is between 15% - 85% (be best to have the tank approximately half full).


Once you have the above parameters set you can go on with the drive cycle which you will need to drive the vehicle between 40 and 65 miles for approximately 15 minutes. This will need to be done a few times which Ford states you need to do 4 stop and go drives which end with idling for at least 30 seconds each time. During the drive cycle try to prevent doing heavy accelerations, holding the accelerator pedal all the way to the ground (known as wide open throttle) and try to prevent any sudden stops. Generally you do not need to drive the vehicle several times to get the monitors to read but if you do all city drives with the fuel tank not at the proper level or all highway driving at speeds over 65 then the vehicle has not gone through the proper cycle to allow you to pass an emissions test.


Here is Fords information on the drive cycle;


NOTE: The IAT PID must be between 10-38°C (50-100°F) during the OBD II drive cycle to enter into all the OBD II monitors. The FLI PID must be between 15% and 85% at all times.

  1. Drive in stop-and-go traffic with at lease 4 idle periods (30 seconds each) while observing the status of the OBD II monitor on the scan tool. If the Exhaust Gas Recirculation (EGR) , Heated Oxygen Sensor (Hops) , Evaporative Emission (EVAP) , Secondary Air (AIR) (if applicable), or catalyst efficiency monitor have not completed, drive on the highway at a constant speed over 64 kph (40 mph) not to exceed 104 kph (65 mph) for up to 15 minutes. Heavy accelerations, sudden decelerations and wide open throttles are not recommended. If the scan tool sends out a three pulse beep at any time, the OBD II drive cycle has completed. NOTE: Vehicles equipped with the EVAP purge flow system or EVAP vapor management flow system monitor do not require EVAP monitor completion to clear the DTC P1000. If the Exhaust Gas Recirculation (EGR) , Heated Oxygen Sensor (HO2S) , Evaporative Emission (EVAP) , Secondary Air Injection (AIR) (if applicable), or catalyst efficiency monitor has not completed, perform the corresponding monitor verification drive cycle.
  2. Bring the vehicle to a stop and retrieve Continuous Memory DTCs to verify the DTC P1000 has been erased.


Keep in mind P1000 is a code that will not set a light and comes on anytime you have cleared the computer of any codes and have not yet gone through a proper drive cycle.


If you have any questions please let me know!