98 engine idle question
Thread Starter
Drifting
Joined: Apr 2014
Posts: 1,396
Likes: 129
From: Plainfield IN
98 engine idle question
My car had the water pump replaced by the PO - the cars idle is a little rough and slightly high - is it possible that it needs the Idle Relearn Procedure done on it.
Moderator, Tech Contributor
Joined: Sep 2013
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From: Cape Coral, Florida
Loose clamp or maybe the rubber boot may be torn...make sure the boot is on securely !!...is not this I would suggest taking your car to a good diagnostic shop !!...Im only guessing here and I dont like to guess diagnosing Corvettes !!
Moderator, Tech Contributor
Joined: Sep 2013
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From: Cape Coral, Florida
Like I said probably in the long run it would be cheaper taking the car to a diagnostic shop where they can plug in a scan tool and see whats going on...without that youre just going to be shot gunning parts and that can get EXPENSIVE !!!
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Le Mans Master
Joined: Aug 2005
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From: CA.
St. Jude Donor '13-'14-'15
If the shop disconnected the battery to do repairs it will need a relearn
Here is the procedure for a C5
1 turn key ON NO start
2 open hood and remove 2 fuses #16 and #23 in the fuse box ( both are 10 amps)
3 Your DIC will now display Check engine ABS etc
4 Turn key OFF
5 re insert both the #16 and 23 fuses
6 Start engine
7 Allow engine to reach operating temperature of at least 176* once there run eng for 5-6 minutes
8 Shut off eng
9 Leave eng OFF and at rest for 30 seconds
10 Re start make sure that the DIC shows no codes ( there should be none)
11 Drive car for a minimum of 30 miles at varying RPM's and speeds This will make the ECM RELEARN and self adjust airflow and IAT's
Here is the procedure for a C5
1 turn key ON NO start
2 open hood and remove 2 fuses #16 and #23 in the fuse box ( both are 10 amps)
3 Your DIC will now display Check engine ABS etc
4 Turn key OFF
5 re insert both the #16 and 23 fuses
6 Start engine
7 Allow engine to reach operating temperature of at least 176* once there run eng for 5-6 minutes
8 Shut off eng
9 Leave eng OFF and at rest for 30 seconds
10 Re start make sure that the DIC shows no codes ( there should be none)
11 Drive car for a minimum of 30 miles at varying RPM's and speeds This will make the ECM RELEARN and self adjust airflow and IAT's
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,319
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From: Cape Coral, Florida
Yes, the idle relearn can also be done after driving some miles !!... if you have a manual trans make sure the AC is OFF, start the car and once the engine coolant temp reaches MORE than 176 degrees idle the engine for 5 minutes and then turn off engine for 30 seconds...that’s it !!...this is out of the FSM. If you have an auto trans same thing but after coolant reaches more than 176 degrees shift trans into drive and allow engine to idle for 5 minutes...now shift into park and idle engine for 5 minutes...turn off engine for 30 seconds !!
Last edited by C5 Diag; Jun 15, 2020 at 04:06 AM.
Le Mans Master
Joined: Aug 2005
Posts: 5,375
Likes: 326
From: CA.
St. Jude Donor '13-'14-'15
Yes It will relearn on it's own but much more slowly ALSO The more bolt ons and mods that you have on your engine the longer it takes to relearn on it's own Often times it may never completely do a full learn on it's own so it's best just to do the procedure - It's very simple---