1987 Nissan 300ZX rough idle

1987 NISSAN 300ZX
100,000 MILES • 6 CYL • 2WD • MANUAL
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BWILKIE
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  • 6 POSTS
when the car is cold it will idle rough. Once the car reaches operating temp it will idle smooth. I realize that when you put a load on the electrcial like the heater fan it will bump the idle up and this will help slightly. I have changed the alternator that was faulty and battery and gave the car a tune up. It is still the same.
Apr 28, 2010 at 4:56 PM
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RASMATAZ
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  • ASE Certified Mechanic
Clean IACV-AAC valve and test the throttle position sensor and the airflow meter
Apr 28, 2010 at 5:11 PM
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RANGERDANGER17
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  • 224 POSTS
wat valves are those mine does the same thing
Jan 3, 2011 at 7:58 PM
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BWILKIE
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  • 6 POSTS
The IACV-AAC valve is bolted on the side of the throttle body, and is attached with three small bolts and has several small hoses, it is the size of a small cell phone.If you gogle it you will find it. I took mine off and srayed it with carburator cleaner and it works a lot better. I did have to adjust my idle speed slighty higher after the cleaning.
Jan 4, 2011 at 3:58 PM
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RASMATAZ
  • ✓ASE Certified Mechanic
  • 75,992 POSTS
  • ASE Certified Mechanic
bwilkie-TY for the donation and for using 2carpros
Feb 2, 2011 at 5:07 PM
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