Engine has a very high idle

1991 BUICK SKYLARK
100,000 MILES • 2.5L • 4 CYL • 2WD • AUTOMATIC
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SNEDWARDS39
  • MEMBER
  • 7 POSTS
It has a very high idle cannot figure it out replaced EGR valve throttle positioning sensor. did a complete tune up new fuel filter. Nothing has seemed to help the idle. when driving down the road it will keep pushing you even when your foot is not on the gas pedal. Checked for vacuum leak did not find any.
Jun 27, 2021 at 7:27 AM
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JACOBANDNICKOLAS
  • ✓ASE Certified Mechanic
  • 110,194 POSTS
  • ASE Certified Mechanic
Hi,

There is a relearn for the IAC, but it requires an OBD1 scan tool. Do me a favor. Take a look at the attachments below. See if performing the minimum idle speed helps.

Let me know if you have questions.

Take care,

Joe

See pics below.
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Jun 27, 2021 at 10:26 PM
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