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Tech / General EngineIs your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!
I'm having trouble with the steps to adjusting/ setting iac and idle. The cap from my idle screw has been removed at a point before I owned the car so I know at some point it's been messed with plus I'm installing a new iac hence the need to make the adjustments. Problem is, it seems the tech article leaves out steps (when to remove a&b ground, is 450rpm base setting in d or p) and from other posts I've seen some people have added their two cents to the procedure but I'm still having problems.
Basically with the iac disconnected my car won't run.
Can I turn the screw to a point where it holds the throttle open to keep the car running and back it down to 450rpm, but again is that in park or drive ?
At what point do I disconnect the ground ?
Can I follow the steps in this post but just turn the screw to keep the car running ?
But I feel that given the car idles at around 800 now in park with where the screw is, it's going to stall before I can set it at 450...
It is usually sufficient to wait 30 seconds for the IAC pintle to fully extend and seat.
Also, there is one step out of sequence. After disconnecting the IAC electrical connector, turn off the ignition and remove the jumper from the "A" and "B" terminals of the ALDL. Do not start the engine with the jumper installed.
It is acceptable to set the minimum air position to achieve 450-500 RPM in DRIVE. Of course, the park brake will have to be set and wheels chocked for safety, and it wouldn't hurt to have an assistant in the vehicle to hold the service brakes.
The last comments are not completely clear. Once the proper throttle minimum air position is set, the TPS voltage should be adjusted to the specified range of 0.54V ± 50mV.
Just get it up to operating temp at idle, turn off all accessories, etc and adjust the blade till you are at 10-15 steps on the IAC. Adjust the TPS to 0.54v +/- 0.07v.
Several years back, I had set my throttle blades by adjusting the IAC pulse count at 12, then tps at .54v I suppose I did it that way because it was easier.
This afternoon I decided to do it the long way with the steps above. To my surprise I had to open the blades quite a bit to get the idle up to 450+rpm in gear.
nearly about 3/4 of a turn! Once I finished the full procedure, I found two things have changed. The initial start up jumps to 1400rpms before settling in, (used to be 1000) & also the iac now sits around 4 counts.
It is usually sufficient to wait 30 seconds for the IAC pintle to fully extend and seat.
Also, there is one step out of sequence. After disconnecting the IAC electrical connector, turn off the ignition and remove the jumper from the "A" and "B" terminals of the ALDL. Do not start the engine with the jumper installed.
It is acceptable to set the minimum air position to achieve 450-500 RPM in DRIVE. Of course, the park brake will have to be set and wheels chocked for safety, and it wouldn't hurt to have an assistant in the vehicle to hold the service brakes.
The last comments are not completely clear. Once the proper throttle minimum air position is set, the TPS voltage should be adjusted to the specified range of 0.54V ± 50mV.
What would be the desired baseline idle speed in a manual trans car? 550-700 in neutral?
