What idle speed is normal??
Team Owner
Joined: Dec 2000
Posts: 90,675
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From: SE NY
Cruise-In II Veteran
Re: What idle speed is normal?? (Daniel DK)
It sounds like the IAC is not working properly. The ECM uses it to allow more air in to maintail the RPM as load increases, such as pulling into gear or turning on accessories. The motor only makes about 5hp at idle in neutral with no accessories running and that alone isn't enough to handle extra loads.
Remove the IAC motor, clean the pintel & bore under the TB as well as the TB plates. Then reassemble and use the set screw on the side of the TB to set base idle (with pintel fully extended) to 450 RPM. If that doesn't do the job, replace the IAM motor.
BTW, my L98, when warmed up, also idles at about 800rpm in neutral and in gear at about 600rpm or so.
Remove the IAC motor, clean the pintel & bore under the TB as well as the TB plates. Then reassemble and use the set screw on the side of the TB to set base idle (with pintel fully extended) to 450 RPM. If that doesn't do the job, replace the IAM motor.
BTW, my L98, when warmed up, also idles at about 800rpm in neutral and in gear at about 600rpm or so.
Team Owner
Joined: Sep 2001
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
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Re: What idle speed is normal?? (65Z01)
mine idles somewhere around 600-700 rpm in D, you might want to check the idle like he said
