thats my mistake, thats my fiances profile. i didnt realize i was signed in on her name!
[LT1] Cannot set Minimum Air (idle)
Thread Starter
Le Mans Master
Joined: Feb 2002
Posts: 7,858
Likes: 2
[LT1] Cannot set Minimum Air (idle)
Tried to set minimum air for idle the other day, 1995 model, had problem. Ran through the procedure as follows:
1. Grounded diagnostic pin (4 to 12) on ALDL (16 pin OBDII style ALDL)
2. Key-on to park IAC pintel to closed position
3. Wait 30 seconds, pulled power plug to IAC while key-on
4. Started engine
Problem was that it idled @ 1500 rpm upon starting up after step 4, and even adjusting the throttle plate idle screw until the plates were all the way closed made no difference, idle remained @ 1500. This has to mean the IAC stayed wide open and did not close.
Why is this?
1. Grounded diagnostic pin (4 to 12) on ALDL (16 pin OBDII style ALDL)
2. Key-on to park IAC pintel to closed position
3. Wait 30 seconds, pulled power plug to IAC while key-on
4. Started engine
Problem was that it idled @ 1500 rpm upon starting up after step 4, and even adjusting the throttle plate idle screw until the plates were all the way closed made no difference, idle remained @ 1500. This has to mean the IAC stayed wide open and did not close.
Why is this?
Last edited by Lone Ranger; Aug 15, 2006 at 01:15 PM.
Racer
Joined: Aug 2006
Posts: 432
Likes: 0
From: Edmond OK
did u make sure the o-ring was on the iac when you put it back on? some come with gaskets, others with o rings. i used both just to be sure. other than that the only other thing i can think of is checking the wiring to the sensor, or actually take it out and conduct your test again and watch to see if it moves properly.
what does it idle at normally?
what does it idle at normally?
Team Owner
Joined: Oct 2000
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From: Fort Knox, KY
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Did you remove the TPS sensor?
If so, get two paper clips, straighten out and slide into the end of the TPS sensor connector, A (earth) and B (tps output), keep the wires separate and turn the ignition on (car off) and measure the voltage with a DIGITAL MULTIMETER at the wires and adjust by loosening the torx bolts, if necessary, to 0.54 volts - this is the normal idle setting.
If so, get two paper clips, straighten out and slide into the end of the TPS sensor connector, A (earth) and B (tps output), keep the wires separate and turn the ignition on (car off) and measure the voltage with a DIGITAL MULTIMETER at the wires and adjust by loosening the torx bolts, if necessary, to 0.54 volts - this is the normal idle setting.
Race Director
Joined: Jun 2004
Posts: 13,966
Likes: 710
From: WI
Originally Posted by Lone Ranger
Tried to set minimum air for idle the other day, 1995 model, had problem. Ran through the procedure as follows:
1. Grounded diagnostic pin (4 to 12) on ALDL (16 pin OBDII style ALDL)
2. Key-on to park IAC pintel to closed position
3. Wait 30 seconds, pulled power plug to IAC while key-on
4. Started engine
Problem was that it idled @ 1500 rpm upon starting up after step 4, and even adjusting the throttle plate idle screw until the plates were all the way closed made no difference, idle remained @ 1500. This has to mean the IAC stayed wide open and did not close.
Why is this?
1. Grounded diagnostic pin (4 to 12) on ALDL (16 pin OBDII style ALDL)
2. Key-on to park IAC pintel to closed position
3. Wait 30 seconds, pulled power plug to IAC while key-on
4. Started engine
Problem was that it idled @ 1500 rpm upon starting up after step 4, and even adjusting the throttle plate idle screw until the plates were all the way closed made no difference, idle remained @ 1500. This has to mean the IAC stayed wide open and did not close.
Why is this?
Race Director
Joined: Jun 2004
Posts: 13,966
Likes: 710
From: WI
Just a quick note, if your car is stock without the coolant bypass mod, it may be easier to make a socket for the IAC. Or maybe a crows foot would fit. If you decide to check the sensor. I took a spare socket, threw it in the vice, and ground on it till it fit. Maybe a cheap thin wall socket would just fit. The socket I ground on can remove the IAC with no problem. Easier then removing the TB in some cases. 
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Thread Starter
Le Mans Master
Joined: Feb 2002
Posts: 7,858
Likes: 2
TPS is .55volts, this is via Datamaster readout w/ key on but engine off. IAC counts (key on engine off) show to be 120 on datamaster, but I've got some sort of problem with the AKM cable and my ALDL, because I can only get data when the engine is not running.
If I start the car with Datamaster running on the laptop and the AKM Cable hooked up, the Service ASR light illuminates and the car shuts off. It stores a code in CCM module 9.1 for Serial Data Link Error (H72) afterwards. This (H72) only happens when I try to log data with datamaster connected and the engine running. So I can't get my IAC counts for when the car is idling
If I start the car with Datamaster running on the laptop and the AKM Cable hooked up, the Service ASR light illuminates and the car shuts off. It stores a code in CCM module 9.1 for Serial Data Link Error (H72) afterwards. This (H72) only happens when I try to log data with datamaster connected and the engine running. So I can't get my IAC counts for when the car is idling
Originally Posted by onedef92
Did you remove the TPS sensor?
If so, get two paper clips, straighten out and slide into the end of the TPS sensor connector, A (earth) and B (tps output), keep the wires separate and turn the ignition on (car off) and measure the voltage with a DIGITAL MULTIMETER at the wires and adjust by loosening the torx bolts, if necessary, to 0.54 volts - this is the normal idle setting.
If so, get two paper clips, straighten out and slide into the end of the TPS sensor connector, A (earth) and B (tps output), keep the wires separate and turn the ignition on (car off) and measure the voltage with a DIGITAL MULTIMETER at the wires and adjust by loosening the torx bolts, if necessary, to 0.54 volts - this is the normal idle setting.
Last edited by Lone Ranger; Aug 16, 2006 at 12:54 PM.
