OBDII failed self test smog test failed

[craigar]

97 SC2 210,000 miles mostly original equipment.
I just failed a California Smog test. It passed all emission requirements with flying colors, however it failed the OBD self test. I ran codes and here are the results.

Misfire monitor - ok
Fuel System mon - ok
Comp component - ok
Catalyst Mon - inc
Htd catalyst - n/a
Evap System mon - n/a
Sec Air System n/a
A/C Refrig Mon - n/a
Oxygen Sens Mon - inc
Oxygen Sens Htr - inc
EGR System mon - inc

The car runs as good as ever. 31 mpg. I changed the ECTS sensor and I cleaned the EGR Valve today. Still, same results. No other codes are indicated. I haven't had the battery disconnected in months. Any ideas?

[rc1488]

Can you get the freeze frame data when it failed?

Also, are these readings taken AFTER you changed the ECTS?

[craigar]

Originally Posted by rc1488

Can you get the freeze frame data when it failed?

Also, are these readings taken AFTER you changed the ECTS?

Readings were taken Both Before and After I changed the temperature sensor, same results. I don't have the freeze frame data from the original failed smog test. Also, the data on my reader (loaner from autozone) doesn't indicate a freeze frame reading. I'll look into how to capture a freeze frame and if I can do it, I'll write back and let you know the results.
Other info that may or may not be of use:
(a) Interior heater takes a long time to warm up, gauge indicates really low car temp. It will eventually get to about 1/4 to 1/3 after an hour of driving. Sounds like the thermostat stays open, could this be a contributor to my other problem? I haven't yet checked to see if there is a change to the gauge reading or the heater since I replaced the ECTS.
(b) Manual Transmission

[Gerry Proctor]

It could be a thermostat, but you should also be seeing a P0128 for failure of engine to come up to temperature fast enough. But that depends on the algorithm to set a code as it varies from car to car and from year to year. Considering the cost, it's worth replacing it to see if that addresses the issue.

What you really need to see is the mode 6 data as well as the freeze frame and pending codes. You will probably not be able to see (and probably won't be able to correctly interpret) these on the lower end scanners. So, without the benefit on that information, you will have to go with the most obvious or likely diagnostic paths and hope you guess right.

The non-continuous monitors need to see sensor data in acceptable ranges in order to successfully run. If one of the senors that contributes to the execution of the monitor test would cause it to fail the test, it won't run the monitor.

In your case, a coolant temp below requirements could very well not allow the monitors to complete since the system won't go into closed loop.

[DonP]

Slow to warm up and unusually low temp gauge readings do indicate a likely stuck open t-stat, and may prevent OBDII diagnostics from a complete check in typical driving to an emissions check scenario.

The P0125 code is for "Insufficient coolant temperature for closed loop fuel control" but the temp limits for it appears to be rather low (~68 F) and a stuck open t-stat may not set it in mild weather.

[craigar]

Originally Posted by Gerry Proctor

I
What you really need to see is the mode 6 data as well as the freeze frame and pending codes. You will probably not be able to see (and probably won't be able to correctly interpret) these on the lower end scanners.

Ok, so today's job is replacing the thermostat, but on a slightly different but related subject. What is the best method for getting the complete OBDII readings including the mode 6 data. Do you simply go to a repair facility and ask for a "read and printout"? Does every shop have the ability? Should I go to a Saturn Dealer? I live in a Rural area with only one repair shop (garage). They are the outfit that did my smog check and were extremely vague, lacking in any explanations as to what the smog failure was about. I sensed that they only wanted the extra diagnostic/repair money. They didn't want to give out any info to help me figure out the problem on my own. Thank you SaturnFans.com!

[Low Saturn]

Originally Posted by craigar

Ok, so today's job is replacing the thermostat, but on a slightly different but related subject. What is the best method for getting the complete OBDII readings including the mode 6 data. Do you simply go to a repair facility and ask for a "read and printout"? Does every shop have the ability? Should I go to a Saturn Dealer? I live in a Rural area with only one repair shop (garage). They are the outfit that did my smog check and were extremely vague, lacking in any explanations as to what the smog failure was about. I sensed that they only wanted the extra diagnostic/repair money. They didn't want to give out any info to help me figure out the problem on my own. Thank you SaturnFans.com!

I have a cable that I can connect the car to my laptop. You can drive around and monitor the readings to see when everything is complete.

[fdryer]

Originally Posted by craigar

(a) Interior heater takes a long time to warm up, gauge indicates really low car temp. It will eventually get to about 1/4 to 1/3 after an hour of driving. Sounds like the thermostat stays open, could this be a contributor to my other problem?

Replace the thermostat.

[rc1488]

Originally Posted by fdryer

Replace the thermostat.

+1. If i remember correctly the car wont go into Closed loop and you fail

[Low Saturn]

You have to do this:

http://www.differentracing.com/forum...ead.php?t=1505

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.