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My son's 2002 325ci has been a real pain to get smogged not due to the emissions part but due to the functional tests. Changed plugs and checked coils and that eliminated all of the misfire codes. Cleared CEL using my Peake reader and it has not gone back on. The smog tech hooked the car up again today and told my son that "two non-continuous" elements were not ready - the catalyst and the O2 sensor heater. He also said that if the O2 sensor heater was ready the catalyst not ready error would go away. This info was being read out of the car's computer. He also said something about error codes that are somehow stored in the computer but don't activate the CEL because they have been cleared and the error has not reoccured. OK, so what is the fix? Do we need to do more cold starts so the computer registers successful O2 sensor heater function a certain number of times? I can hook up my Peake reader but it doesn't sound as if it will read anything. I don't want to re-clear the computer with the Peake reader because that means my son has to drive it another 150 miles or so just to get enough data into it on the engine's operation so it will be able to be smogged. Any suggestions?

:banghead:
 

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If you don't meet all the test conditions you could drive hundreds of miles and not be ready for a smog check... Try the following:

OBD-II Driving Cycle
If you have a 96 or newer vehicle you have the OBD-II diagnostic system. This system is constantly monitoring the sensors and solenoids on the engine. If you have replaced the battery, disconnected the battery or cleared the codes after making a repair you will need to do what is called a "Driving Cycle". This will perform a diagnostic on all the systems the computer monitors. This cycle can be done in under fifteen minutes.

To perform an OBDII Driving cycle do the following:

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.
 

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I find that if you live in the city as I do, it is impossible to meet these conditions exactly. This is killing me!
 

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I find that if you live in the city as I do, it is impossible to meet these conditions exactly. This is killing me!
BTW, 2 year old post your digging up here.

Not the case, but you will have to cruise a bit on open road at 45-65 MPH and not go above 3k RPM. If your car cannot clear the Readiness Monitors in 2-3 cold starts with a 10 mile run added in, there is a PROBLEM.

See attached PDF for more info.
 

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Sorry for the forum faux pas but while I wait for the post to deliver my tech, I've been searching the posts for something I might have missed.

BTW, 2 year old post your digging up here.

Not the case, but you will have to cruise a bit on open road at 45-65 MPH and not go above 3k RPM. If your car cannot clear the Readiness Monitors in 2-3 cold starts with a 10 mile run added in, there is a PROBLEM.

See attached PDF for more info.
 

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Here is some light reading for you, note your problem may not be as big of an issue as this Fanatics was, it gives you insight on exactly how fingerprinting or trending the O2 sensors with a graph can allow you to find and resolve issues - http://forum.e46fanatics.com/showthread.php?t=954362
 
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