C5 Idle Relearn Procedure
Thread Starter
Melting Slicks
Joined: May 2007
Posts: 2,113
Likes: 0
From: Houston TX
C5 Idle Relearn Procedure
I posted a thread a while back about my high idle after a ported stock LS1 TB install.On every start up,I am getting idles in the 1200-1500 range and drops back down into the normal 600-700 range after about 30 seconds.I used this procedure:
http://www.c5forum.com/diy/idlerelearn.php
and still,I have the same high idle problem.Anyone know is that procedure is correct and/or how to fix the high idle?
http://www.c5forum.com/diy/idlerelearn.php
and still,I have the same high idle problem.Anyone know is that procedure is correct and/or how to fix the high idle?
Instructor
Joined: Aug 2007
Posts: 158
Likes: 0
From: DFW Big State Of Texas
Did you haver the car tunned when you installed the throttle body?
You can disconecct the plug going to the throttle body turn on car for 20 sec You wil throw a code. Turn off car plug back in start car Clear code, let idle for 10 min with a/c off and 10 min with a/c on.
You can disconecct the plug going to the throttle body turn on car for 20 sec You wil throw a code. Turn off car plug back in start car Clear code, let idle for 10 min with a/c off and 10 min with a/c on.
Thread Starter
Melting Slicks
Joined: May 2007
Posts: 2,113
Likes: 0
From: Houston TX
no tune.When you say disconnect the plug, which plug?The 6 pin connector thing?
Burning Brakes
Joined: Jul 2006
Posts: 968
Likes: 12
From: Regina Sask
The car will learn the idle once the ECT is at 176*F. This is the temp required for the LTIT (Long Term Idle Trim) to open or close the throttle blade in order to get the STIT (Short Term Idle Trim) close to 0 g/sec.
The idle learn procedure pretty much happens in a few min at operating temp. I tune the GM vehicles with Hp Tuners, and never had to perform the idle learn as per the GM manual.
If the idle speed is high after ported the TB, this means that there was too much material removed so that there is gap between the edge of the throttle blade & the bore. Other that reducing the base running airflow table in the tune, you will need to find another TB & start over.
Russ Kemp
The idle learn procedure pretty much happens in a few min at operating temp. I tune the GM vehicles with Hp Tuners, and never had to perform the idle learn as per the GM manual.
If the idle speed is high after ported the TB, this means that there was too much material removed so that there is gap between the edge of the throttle blade & the bore. Other that reducing the base running airflow table in the tune, you will need to find another TB & start over.
Russ Kemp
Safety Car
Joined: Oct 2000
Posts: 4,949
Likes: 10
From: Monticello MN
The car will learn the idle once the ECT is at 176*F. This is the temp required for the LTIT (Long Term Idle Trim) to open or close the throttle blade in order to get the STIT (Short Term Idle Trim) close to 0 g/sec.
The idle learn procedure pretty much happens in a few min at operating temp. I tune the GM vehicles with Hp Tuners, and never had to perform the idle learn as per the GM manual.
If the idle speed is high after ported the TB, this means that there was too much material removed so that there is gap between the edge of the throttle blade & the bore. Other that reducing the base running airflow table in the tune, you will need to find another TB & start over.
Russ Kemp
The idle learn procedure pretty much happens in a few min at operating temp. I tune the GM vehicles with Hp Tuners, and never had to perform the idle learn as per the GM manual.
If the idle speed is high after ported the TB, this means that there was too much material removed so that there is gap between the edge of the throttle blade & the bore. Other that reducing the base running airflow table in the tune, you will need to find another TB & start over.
Russ Kemp
Instructor
Joined: Aug 2007
Posts: 158
Likes: 0
From: DFW Big State Of Texas
Had to do it to mine when I put my ported and polished one from Mark Shraner. He was the one who told me the procedure.
Thread Starter
Melting Slicks
Joined: May 2007
Posts: 2,113
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From: Houston TX
I REALLY hope this works.....I don't think 1500 rpm cold starts are to healthy for my motor.
Le Mans Master
Joined: Dec 2006
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From: Phoenix Arizona
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Thread Starter
Melting Slicks
Joined: May 2007
Posts: 2,113
Likes: 0
From: Houston TX
Alright I just did the procedure.I disconnected the connector and started the car.The idle jumped up to 2000 and I let it run for a bit and shut it down then reconnected the connector.I restarted the car and the idle was sitting at the 1500 range still and after 30 seconds or so would drop to about 800 rpm this time, just as it did prior but 200 rpm's higher.
Did I do it correctly or what....
Safety Car
Joined: Oct 2000
Posts: 4,949
Likes: 10
From: Monticello MN
Here's one I have that I have successfully used:
The car will re-learn simply by driving it between 50-100 miles. Or, the actual way to do it more quickly, is the following procedure:
1) Insert key into ignition and turn to the “ON” position, but, DO NOT START THE ENGINE.
2) Open the engine compartment fuse box cover and remove the two 10 amp fuses from position numbers 16 & 23.
a) According to the manual there are two fuse boxes. Use the engine compartment fuse block for this procedure not the instrument panel fuse block.
b) Engine Compartment Fuse Block (correct one): 16 is Powertrain Control Module A and 23 is Powertrain Control Module B.
c) Instrument panel fuse block (wrong one): 16 is Air Bag, 22 is Body Control Module-Ignition and 23 is Body Control Module-Ignition 2.
NOTE: Your DIC will now display “check” messages for ABS, etc… Do not worry as this is normal.
3) Turn the ignition key to the “OFF” position.
4) Return to the engine compartment fuse box and re-insert both 10 amp fuses for positions 16 & 23.
5a) Idle relearn for an M6:
1) Start the engine and allow the coolant temp to reach a minimum of 176 degrees F. Allow the engine to run at this minimum temperature for at least 5 minutes.
2) After the 176 degree, 5 minute minimum run, shut down the engine for a minimum of 30 seconds.
3) Restart the engine and check for DIC error codes (there should be none).
5b) Idle relearn for an A4: (different)
1) Start the engine and allow the coolant temp to reach a minimum of 176 degrees F. Allow the engine to run at this minimum temperature for at least 5 minutes.
2) Allow the car to idle in DRIVE, with air ON and then OFF, for 5 minutes each, and then in NEUTRAL, with air ON and then OFF, for 5 minutes each.
3) Turn the car off for at least 30 seconds.
4) Restart the engine and check for DIC error codes (there should be none).
6) Drive car for a minimum of 30 miles at varying rpm settings and speeds. PCM will now re-learn and adjust for the new air flow and temperature at the intake.
a) If error codes persist, repeat steps 1-7. Make sure fuses are properly inserted before repeating steps.
b) Do not deviate from the sequence outlined above. If you do, restart the sequence from scratch.
c) Steps 1-4 are also necessary if you ever disconnect your battery or lose power for any reason.
Good luck!
Ed
The car will re-learn simply by driving it between 50-100 miles. Or, the actual way to do it more quickly, is the following procedure:
1) Insert key into ignition and turn to the “ON” position, but, DO NOT START THE ENGINE.
2) Open the engine compartment fuse box cover and remove the two 10 amp fuses from position numbers 16 & 23.
a) According to the manual there are two fuse boxes. Use the engine compartment fuse block for this procedure not the instrument panel fuse block.
b) Engine Compartment Fuse Block (correct one): 16 is Powertrain Control Module A and 23 is Powertrain Control Module B.
c) Instrument panel fuse block (wrong one): 16 is Air Bag, 22 is Body Control Module-Ignition and 23 is Body Control Module-Ignition 2.
NOTE: Your DIC will now display “check” messages for ABS, etc… Do not worry as this is normal.
3) Turn the ignition key to the “OFF” position.
4) Return to the engine compartment fuse box and re-insert both 10 amp fuses for positions 16 & 23.
5a) Idle relearn for an M6:
1) Start the engine and allow the coolant temp to reach a minimum of 176 degrees F. Allow the engine to run at this minimum temperature for at least 5 minutes.
2) After the 176 degree, 5 minute minimum run, shut down the engine for a minimum of 30 seconds.
3) Restart the engine and check for DIC error codes (there should be none).
5b) Idle relearn for an A4: (different)
1) Start the engine and allow the coolant temp to reach a minimum of 176 degrees F. Allow the engine to run at this minimum temperature for at least 5 minutes.
2) Allow the car to idle in DRIVE, with air ON and then OFF, for 5 minutes each, and then in NEUTRAL, with air ON and then OFF, for 5 minutes each.
3) Turn the car off for at least 30 seconds.
4) Restart the engine and check for DIC error codes (there should be none).
6) Drive car for a minimum of 30 miles at varying rpm settings and speeds. PCM will now re-learn and adjust for the new air flow and temperature at the intake.
a) If error codes persist, repeat steps 1-7. Make sure fuses are properly inserted before repeating steps.
b) Do not deviate from the sequence outlined above. If you do, restart the sequence from scratch.
c) Steps 1-4 are also necessary if you ever disconnect your battery or lose power for any reason.
Good luck!
Ed
Last edited by C5XTASY; Dec 17, 2007 at 08:37 AM.
Instructor
Joined: Aug 2007
Posts: 158
Likes: 0
From: DFW Big State Of Texas
mobil1 10w30
Alright I just did the procedure disconnected the connector and started the car.The idle jumped up to 2000 and I let it run for a bit and shut it down then reconnected the connector.I restarted the car and the idle was sitting at the 1500 range still and after 30 seconds or so would drop to about 800 rpm this time, just as it did prior but 200 rpm's higher.
Did I do it correctly or what....
Alright I just did the procedure disconnected the connector and started the car.The idle jumped up to 2000 and I let it run for a bit and shut it down then reconnected the connector.I restarted the car and the idle was sitting at the 1500 range still and after 30 seconds or so would drop to about 800 rpm this time, just as it did prior but 200 rpm's higher.
Did I do it correctly or what....
I haven't had a stock idle since my car was new i have a cam.
Drive it for a few days with a/c off and when it is on and see how the car behaves.
Last edited by PFMC3; Dec 17, 2007 at 11:19 AM.
Racer
Joined: Sep 2000
Posts: 373
Likes: 0
From: Wakefield R.I.
Russ K is correct you need another t.body.
You never said who did the job on this one. If its a Shanner get a hold of him, I know he will help fix the issue(doubt its his). If its not one of his then get another unit and send it off to Mark and your problems will be solved. Mark is the man RE: Throttle bodies.
You never said who did the job on this one. If its a Shanner get a hold of him, I know he will help fix the issue(doubt its his). If its not one of his then get another unit and send it off to Mark and your problems will be solved. Mark is the man RE: Throttle bodies.
Thread Starter
Melting Slicks
Joined: May 2007
Posts: 2,113
Likes: 0
From: Houston TX
Russ K is correct you need another t.body.
You never said who did the job on this one. If its a Shanner get a hold of him, I know he will help fix the issue(doubt its his). If its not one of his then get another unit and send it off to Mark and your problems will be solved. Mark is the man RE: Throttle bodies.
You never said who did the job on this one. If its a Shanner get a hold of him, I know he will help fix the issue(doubt its his). If its not one of his then get another unit and send it off to Mark and your problems will be solved. Mark is the man RE: Throttle bodies.
Thread Starter
Melting Slicks
Joined: May 2007
Posts: 2,113
Likes: 0
From: Houston TX
