idle fluctuates up and down when in gear and stopped

1979 LINCOLN MARK V
80,000 MILES • 6.6L • V8 • AUTOMATIC
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RONALD TROXELL
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  • 5 POSTS
My Lincoln drives like new until I stop for red light or stop sign. Then the idle starts up and down up and down when in gear. Much worse when in neutral.
Oct 24, 2016 at 6:08 PM
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HMAC300
  • ✓ASE Certified Mechanic
  • 48,601 POSTS
  • ASE Certified Mechanic
try cleaning throttle plate on both sides and IAC hole with choke cleaner. also, check for vacuum leaks like a cracked hose or one off etc.
Oct 25, 2016 at 6:25 AM
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RONALD TROXELL
  • MEMBER
  • 5 POSTS
Thanks. I do not know what the IAC hole is or where it is located?
Oct 25, 2016 at 1:44 PM
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HMAC300
  • ✓ASE Certified Mechanic
  • 48,601 POSTS
  • ASE Certified Mechanic
it's the idle air control motor but it's a n oblong hole in throttle body you'll see it
Oct 25, 2016 at 4:29 PM
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