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Discussion Starter #1
I am pretty fed up with this GM drive cycle .. i have tried to complete it in everyway and my catalyst is still "not ready" Trying to follow its instructions here in California sucks ass . For one nobody drives 55 2 there isnt enough open space to go from 55 to 20 coasting with out hitting the brakes . I dont understand why i cant put it on the dyno and run it . I have already paid the smog fee and my tags but i cant at all get them until i pass the ready test.All it needs is one out of the 2 to go ready and i cant for the life of me get it to become "ready". I have drove it over 200 miles since and i dont wanna keep driving long distances if this isn't gonna work . What gives? Any advice would be great .
 

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Tin Indian
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Huh?????? It must be a California thing?
 

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With the things you have installed (especially the headers), as well as some level of tune performed, maybe your tuner has shutdown the downstream H02 sensors. If he did, an *If* those sensors are required to communicate with the ECM when the smog check is being performed, you'll never reach that *all monitors ready* condition. When I went in for my first required test, I plugged in my code reader and had the green (all monitors ready) light illuminated in seconds. It stayed good all the way to the shop. On restart (with their equipment plugged in), it passed with no problems. But I'm also stock, so I know all the monitors *are* active.
 

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Discussion Starter #7
With the things you have installed (especially the headers), as well as some level of tune performed, maybe your tuner has shutdown the downstream H02 sensors. If he did, an *If* those sensors are required to communicate with the ECM when the smog check is being performed, you'll never reach that *all monitors ready* condition. When I went in for my first required test, I plugged in my code reader and had the green (all monitors ready) light illuminated in seconds. It stayed good all the way to the shop. On restart (with their equipment plugged in), it passed with no problems. But I'm also stock, so I know all the monitors *are* active.

The 02 sensors are active if they were turned off the test would show not available however they are saying that they are just not ready . The headers are off the car and stock exhaust is on the car . I had a hunch because of the 160 stat that was in it was making it run way to cool i seen on a warm day about 180 max. i know the ecu needs to see around 200-205 to operate so i threw in the stock one. I did run it up some hills and let it coast to a stop like everyone has been saying . All i need is one sensor to complete and im good to go . Im just not sure why it isnt wanting to test.
 

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Discussion Starter #8
I wanted to add this is what im missing and its very hard to drive 55 mph for 5 min . I will have to find a real open road to try this .



Catalyst Monitor Drive Cycles

The following are some sample drive cycles for the catalyst monitor to run:

Ford: The catalyst monitor will not run until the HEGO (oxygen sensor) monitor has run and completed successfully with no faults found. The vehicle must then be driven in stop-and-go traffic conditions at five different cruise speeds ranging from 25 to 45 mph over a period of 10 minutes.

GM: The catalyst monitor runs after cruising at 55 mph for 5 minutes, but it make take up to five drive cycles at this speed before the monitor will run!

Chrysler: The catalyst monitor will NOT run unless the Check Engine light is off, no fault codes are present, the fuel level is between 15 and 85 percent full, and the coolant temperature is above 70 degrees F. If these conditions have been met, the engine must have run at least 90 seconds, and the engine speed must be between 1,350 and 1,900 rpm. Idle vehicle for five minutes (to reach closed loop operation), the drive at a steady speed between 30 and 45 mph for two minutes.

Toyota: The catalyst monitor will run after driving the vehicle at 40 to 55 mph for seven minutes, followed by driving at 35 to 45 mph for another seven minutes.
 

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My suggestion would be to go out late at night when there aren't ten million people out on the roads so you get it all to yourself and can drive whatever speed you want... if you haven't already found a solution, anyway.
 

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Just returned from my required smog check. For sure all cars 2000 an up *only* require the DLC hookup procedure in this state.You are also allowed to have a *not ready* EVAP condition, an *it* will not prevent passing the smog test. All other assigned readness items must work as advertised (forgot to ask if the downstream HO2 sensors could be turned off, or must function correctly). Having a fault code displayed against the EVAP system, most likely would cause a no pass condition.
I had a very serious older man performing the test on my car. *HE* looked at *everything*. Up to an including getting down on a knee mat with a large (long handled) mirror, an verifying that I had all 4 catalytic converters (with readable info on them) to verify that they were legal. He said you could have any exhaust you want *beyond* the converters. They said you could headers, air intake, etc. installed, as long as those items were CARB approved. An this place *knows* which items are, an are not approved. So if your on the edge with some of these items, you best locate a place that is customer friendly.
 

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I have Evaporative Emissions Control System and O2 sensors not ready. I've driven the stupid thing over 1000 miles in all driving conditions and it still won't pass! Car is a bone stock G8 GT except for an Orssom CAI.
Colin
 

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How are you finding out that those 2 emission monitors are "not" ready. ? Do you know "if" those 2 monitors were failing prior to installing that catch can system ? Since your not saying you have a check engine light illuminated, it gives the impression that all of the components are working correctly. Are you sure that you did not tune out something that normally woud report to the ECM that it tested OK an is in a ready mode ? I don't know if all 4 of the the H02's are monitored an required to make the H02 circuit reach the ready state condition. Maybe it could even be one or more tired H02 sensors. Not bad enough to set a fault code, but having a tough time cycling the voltage as needed in a timely manner. Even having a very weak internal heating element, would be bad news for the sensor.
 

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Found this tidbit of information online, may be worthwhile to take a gander and presume it's still applicable.
NOTE: If monitors fail to become ready after performing drive cycle, then either there is a low voltage condition to the onboard computer or the catalytic converter is marginal and needs to be replaced
ok, unfortunately many people, including emission testers, erroneously believe that completing the drive cycle to set the monitors to readiness is based upon mileage. It is NOT. It is condition based. Below is the exact drive cycle to perform. You MUST do it exactly as stated and in the order given:

GM Specific drive cycle to set the OBD2 monitors to readiness state:
  1. Cold Start. In order to be classified as a cold start the engine coolant temperature must be below 50°C (122°F) and within 6°C (11°F) 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 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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Gopherit, I have been to my local test station twice within 10 days, same codes both trips. Car is bone stock, problem stems from disconnecting the battery to replace the starter motor I believe.
Great info, Pony Man, going to try that! Thanks.
 

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Just get someone to load a tune on the car with all the monitors set to ready. People do it for inspection purposes all the time. Myself included.
 

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Now have 3000 miles and same 2 "not ready" codes. Dealer hooked it up to their computer, can find nothing wrong! Told me to keep on driving. Tried to do the tests listed above, the 55mph part impossible where I live. This getting old!:rolleyes:
Colin
 
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