CA smog Drive Cycle for new AT4

[At430]

I bought a new 2024 GMC AT4 Diesel out of state and received it today. It had 17 miles on it. I contacted a smog shop and asked if it needed some drive time on it before I got it smogged. They stated since it’s all done through the electrical equipment that I did not need to do that for it to pass.

Anyways, I tried to get it smogged and it obviously failed. The tech said that before the dealership shipped the truck they reset the monitor and that I would need to contact the dealer to find out the drive cycle to have it be able to pass.

Any members here have any experience with this happening to them in a brand new diesel truck and know the drive cycle process (how long it needs to be driven/ speeds and timing.) The out of state dealer has not gotten back to me regarding the issue and I need to register the truck lol.

Thanks in advance

 

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[yzf1999]

Can’t the closest GMC or Chevrolet dealer give you the info you need?…All cars and trucks are the same (50 state compliance).

 

[gemarsh]

I bought a new 2024 GMC AT4 Diesel out of state and received it today. It had 17 miles on it. I contacted a smog shop and asked if it needed some drive time on it before I got it smogged. They stated since it’s all done through the electrical equipment that I did not need to do that for it to pass.

Anyways, I tried to get it smogged and it obviously failed. The tech said that before the dealership shipped the truck they reset the monitor and that I would need to contact the dealer to find out the drive cycle to have it be able to pass.

Any members here have any experience with this happening to them in a brand new diesel truck and know the drive cycle process (how long it needs to be driven/ speeds and timing.) The out of state dealer has not gotten back to me regarding the issue and I need to register the truck .

Duck duck go is your friend...

OBD II Drive Cycle for GM | JUST SMOGS® + Repair

OBD II Drive Cycle complete all readiness monitors for smog check. General Motors: GM, Chevrolet, Buick, Oldsmobile, Pontiac, Saturn

justsmogs.com

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.

 

[At430]

Duck duck go is your friend...

OBD II Drive Cycle for GM | JUST SMOGS® + Repair

OBD II Drive Cycle complete all readiness monitors for smog check. General Motors: GM, Chevrolet, Buick, Oldsmobile, Pontiac, Saturn

justsmogs.com

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.

Thanks, I did see that sequence but didn’t know if that would be the drive cycle for a brand new truck. I’ll try to find a area to do all that, but who knows lol