Once per trip tests?
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Once per trip tests?
so since i got HP Tuners i have noticed that my Evaporative system test is always incomplete, that means i now have 3 incomplete tests and cannot pass inspection. the others are my catalyst and O2 sensor heater. is there any way to fix these problems. the Catalyst is probably gonna stay since i dont have any, and the heater test should be taken care of when i change my O2 sensors, but its the Evap that concerns me. what is this and how can i fix it?
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You have to complete a driving cycle. Some of the tests can not be checked until the engine is in a certin state....
GM driving cycle......
GM driving cycle......
General Motors Driving Cycle
A complete driving cycle should perform diagnostics on all systems. A complete driving 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 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.
A complete driving cycle should perform diagnostics on all systems. A complete driving 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 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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awesome info! i knew there was some kind of way to get it to perform the tests, but i had no idea it was done like that. i will give that a try before work tomorrow and see if i still have all those nasty incompletes.
Also, what about when i get it inspected? chances are they are gonna shut my truck off at the inspection place, so can some OBD II scanners force these tests so they dont have to go drive your car around to get those tests to run?
Again thanks for the great info
Also, what about when i get it inspected? chances are they are gonna shut my truck off at the inspection place, so can some OBD II scanners force these tests so they dont have to go drive your car around to get those tests to run?
Again thanks for the great info
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awesome info! i knew there was some kind of way to get it to perform the tests, but i had no idea it was done like that. i will give that a try before work tomorrow and see if i still have all those nasty incompletes.
Also, what about when i get it inspected? chances are they are gonna shut my truck off at the inspection place, so can some OBD II scanners force these tests so they dont have to go drive your car around to get those tests to run?
Again thanks for the great info
Also, what about when i get it inspected? chances are they are gonna shut my truck off at the inspection place, so can some OBD II scanners force these tests so they dont have to go drive your car around to get those tests to run?
Again thanks for the great info
I THINK the scanner they use will just look at the history of the tests, and make sure it has completed all test (and past) in the past...
But I'm not 100%
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ahh that would make sense. kinda makes me wish the VCM scanner in HP Tuners had more capabilities that the scanners have. ex. looking up the misfire history. (i dont know of any way to so)
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