Idle Relearn
Thread Starter
Pro
Joined: Apr 2002
Posts: 567
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From: Gresham OR
Idle Relearn
This is probably in my owner's manual, but how do you do an "idle relearn" of the computer system? I am considering the K&N filter w/ ZO6 lid and have seen comments about the computer taking a couple of hundred miles to adjust and that the process can be speeded up with the idle relearn.
Advanced
Joined: Mar 2002
Posts: 64
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From: San Ramon CA
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Re: Idle Relearn (borba)
I am not clear on the need for this. I can see driving around for a couple of hundred miles to relearn all the cells in the computer, but for idle the cell should change very quickly. If you remove power, all the cells are then defaulted and need to relearn anyhow. So, what difference does it make to either plug in the filter and go or clear the computer block learn values? I am confused :crazy: and would like to hear a good technical explanation of why the relearn process is necessary at all for a filter change.
Burning Brakes
Joined: Nov 2001
Posts: 1,161
Likes: 81
From: Bel Air MD
Re: Idle Relearn (vettenuts)
Here is the procedure from the GM service manual for a 1999:
GM Service Manual – 1999 Corvette
Idle Learn Procedure
Anytime the powertrain control module (PCM) or the battery is disconnected, the PCM loses power, or the PCM is reprogrammed, the PCMs learned idle position is lost. The engine idle is unstable when the learned idle position is lost.
Perform the following procedure in order to return the learned idle to the correct position:
Automatic Transmission
1. Turn OFF the ignition.
2. Restore the PCM battery feed.
3. Turn OFF the A/C controls.
4. Set the parking brake and block the drive wheels.
5. Start the engine.
6. Ensure that the engine coolant temperature is more than 80°C (176°F).
7. Shift the transmission into Drive.
8. Allow the engine to idle for 5 minutes.
9. Shift the transmission into Park.
10. Allow the engine to idle for 5 minutes.
11. Turn OFF the engine for 30 seconds.
Manual Transmission
1. Turn OFF the ignition.
2. Restore the PCM battery feed.
3. Turn OFF the A/C controls.
4. Set the parking brake and block the drive wheels.
5. Place the transmission in Neutral.
6. Start the engine.
7. Ensure that the engine coolant temperature is more than 80°C (176°F).
8. Allow the engine to idle for 5 minutes.
9. Turn OFF the engine for 30 seconds.
GM Service Manual – 1999 Corvette
Idle Learn Procedure
Anytime the powertrain control module (PCM) or the battery is disconnected, the PCM loses power, or the PCM is reprogrammed, the PCMs learned idle position is lost. The engine idle is unstable when the learned idle position is lost.
Perform the following procedure in order to return the learned idle to the correct position:
Automatic Transmission
1. Turn OFF the ignition.
2. Restore the PCM battery feed.
3. Turn OFF the A/C controls.
4. Set the parking brake and block the drive wheels.
5. Start the engine.
6. Ensure that the engine coolant temperature is more than 80°C (176°F).
7. Shift the transmission into Drive.
8. Allow the engine to idle for 5 minutes.
9. Shift the transmission into Park.
10. Allow the engine to idle for 5 minutes.
11. Turn OFF the engine for 30 seconds.
Manual Transmission
1. Turn OFF the ignition.
2. Restore the PCM battery feed.
3. Turn OFF the A/C controls.
4. Set the parking brake and block the drive wheels.
5. Place the transmission in Neutral.
6. Start the engine.
7. Ensure that the engine coolant temperature is more than 80°C (176°F).
8. Allow the engine to idle for 5 minutes.
9. Turn OFF the engine for 30 seconds.
