Miata ECM/CEL question

Anybody know how long it takes the Miata OBDII status to clear and reset?

I've got the Manic Miata in her Depressive Miata phase so I can sneak it through state inspection. Fired her up last night and she runs pretty well; not throwing any codes or CEL yet. I have the blower bypass wired open and the original sensors back in place.

Most of the status monitors are reporting OK on the scan tool, but O2 Monitoring and EGR are both reporting "incomplete". I let it idle for about 15 minutes, and drove it about 5 miles; operating temperature appeared to be about 195.

Any idea of how much more I need to drive it before those two status tests are complete? Thanks!

Using this guide worked for me (from miata.net: http://forum.miata.net/vb/showthread.php?t=470475):

1. Cold Start - In order to be classified as a cold start the engine coolant temperature must be below 50ºC (122ºF) and within 6ºC (11ºF) of the ambient air temperature at startup. Do not leave the key on prior to the cold start or the heated oxygen sensor diagnostic may not run.

2. Idle - The engine must be run for two and a half minutes with the air conditioner on maximum and rear defroster on. The more electrical load you can apply the better. This will test the O2 heater, Passive Air, Purge "No Flow", Misfire and if closed loop is achieved, Fuel Trim.

3. Accelerate - Turn off the air conditioner and all the other loads and apply half throttle until 88km/hr (55mph) is reached. During this time the Misfire, Fuel Trim, and Purge Flow diagnostics will be performed.

4. Hold Steady Speed - Hold a steady speed of 88km/hr (55mph) for 3 minutes. During this time the O2 response, air Intrusive, EGR, Purge, Misfire, and Fuel Trim diagnostics will be performed.

5. Decelerate - Let off the accelerator pedal. Do not shift, touch the brake or clutch. It is important to let the vehicle coast along gradually slowing down to 32km/hr (20 mph). During this time the EGR, Purge and Fuel Trim diagnostics will be performed.

6. Accelerate - Accelerate at 3/4 throttle until 88-96 km/hr (55-60mph). This will perform the same diagnostics as in step 3.

7. Hold Steady Speed - Hold a steady speed of 88km/hr (55mph) for five minutes. During this time, in addition to the diagnostics performed in step 4, the catalyst monitor diagnostics will be performed. If the catalyst is marginal or the battery has been disconnected, it may take 5 complete driving cycles to determine the state of the catalyst.

8. Decelerate - This will perform the same diagnostics as in step 5. Again, don't press the clutch or brakes or shift gears.

Wow, that is truly excellent information. Thank you!

The requirements is that it completes all of the test during an FTP 75. You can look up what the drive is, but it's only about 11 miles in length with a 10 min soak between the first 8 and the last 3.

And for sure it will start if you keep the start temp between 68F and 80F.

10 minute soak meaning sitting there idling, or turned off, or...? Thanks!

Duke wrote: 10 minute soak meaning sitting there idling, or turned off, or...? Thanks!

Off.