IAC adjustment
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From: Springboro, Pa.
Car: 1987 Monte Carlo SS
Engine: Vortec headed 350
Transmission: '89 WC T5
Axle/Gears: 3.73
IAC adjustment
Does anyone have a better link/info to how to set the IAC properly? The one in the tech section doesn't explain when exactly a person should unjumper A&B and I'm going to assume you don't leave it jumpered forever. It explains when to jumper it, but never mentions anything about removing it 
Also, going by the instructions, I now have a car that idles at 1500 rpms in park and 1000 rpms in gear
So I guess I would like any info that could help me do this correctly and not have obvious missing steps.
Thanks.

Also, going by the instructions, I now have a car that idles at 1500 rpms in park and 1000 rpms in gear

So I guess I would like any info that could help me do this correctly and not have obvious missing steps.
Thanks.
Thread Starter
Member
iTrader: (7)
Joined: Dec 2007
Posts: 133
Likes: 0
From: Springboro, Pa.
Car: 1987 Monte Carlo SS
Engine: Vortec headed 350
Transmission: '89 WC T5
Axle/Gears: 3.73
Re: IAC adjustment
Ok, nevermind. I found some better info.
The write up in the tech section lacks important info.
The write up in the tech section lacks important info.
Thread Starter
Member
iTrader: (7)
Joined: Dec 2007
Posts: 133
Likes: 0
From: Springboro, Pa.
Car: 1987 Monte Carlo SS
Engine: Vortec headed 350
Transmission: '89 WC T5
Axle/Gears: 3.73
Re: IAC adjustment
"The idle stop screw is the small screw that is mounted on the side of the throttlebody.
Step 1: Remove the small cap covering the screw (T20 torx) if it is still present.
Step 2: Now connect the ALDL teminals A & B with a a paper clip or small wire.
Step 3: Now turn the key on but DO NOT START THE ENGINE and wait at least 30 seconds.
Step 4: With the key still ON and the engine OFF, disconnect the IAC connector.
Step 5: Disconnect the Set Timing connector.
Step 6: Now start the engine and let it go into closed loop. You should still have the wire in the ALDL connector. The check engine light will start flashing 2.5 times a second when it is in open loop but will slow down alot when it goes into closed loop.
Step 7: Remove the wire at the ALDL connector, and turn the TORX#20 screw(idle speed screw) to get about 450-500 rpm with trans in park or neutral.
Step 8: Turn engine off and reconnect the set timing connector and the IAC connector. Then restart engine and clear out any codes from the ECM."
I didn't really feel like typing all of that when I posted above since I am a very SLOW typer
Step 1: Remove the small cap covering the screw (T20 torx) if it is still present.
Step 2: Now connect the ALDL teminals A & B with a a paper clip or small wire.
Step 3: Now turn the key on but DO NOT START THE ENGINE and wait at least 30 seconds.
Step 4: With the key still ON and the engine OFF, disconnect the IAC connector.
Step 5: Disconnect the Set Timing connector.
Step 6: Now start the engine and let it go into closed loop. You should still have the wire in the ALDL connector. The check engine light will start flashing 2.5 times a second when it is in open loop but will slow down alot when it goes into closed loop.
Step 7: Remove the wire at the ALDL connector, and turn the TORX#20 screw(idle speed screw) to get about 450-500 rpm with trans in park or neutral.
Step 8: Turn engine off and reconnect the set timing connector and the IAC connector. Then restart engine and clear out any codes from the ECM."
I didn't really feel like typing all of that when I posted above since I am a very SLOW typer
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