Thank you- found a plate and ordered it with gaskets.
When hot and you unplug the IAC your idle should drop to about 800 plus or minus depending how someone set the throttle plate stop screw. I presume you have an OEM Ford throttle body with no other adjustments.
If it does not drop, you may have a vacuum leak. Check the hose to the PCV and make sure the valve is in the pocket where it belongs. Also make sure the valve works as it should- blocks air in one direction and lets it flow in the other.
If it does drop but jumps back up when you plug the IAC back in, you likely do not have a vacuum leak. Something is telling the computer to raise the RPM by opening the IAC.
If you adjust the settings for the throttle stop to set the idle speed with the IAC unplugged, after you are done you should unplug your battery and the spout connector for about 30 minutes to activate a learn cycle. The throttle plate should never close completely otherwise it can stick.
I solved idle hanging by reducing the idle speed with the IAC disconnected.
My current problem is surging when you let up lightly on the accelerator.
When hot and you unplug the IAC your idle should drop to about 800 plus or minus depending how someone set the throttle plate stop screw. I presume you have an OEM Ford throttle body with no other adjustments.
If it does not drop, you may have a vacuum leak. Check the hose to the PCV and make sure the valve is in the pocket where it belongs. Also make sure the valve works as it should- blocks air in one direction and lets it flow in the other.
If it does drop but jumps back up when you plug the IAC back in, you likely do not have a vacuum leak. Something is telling the computer to raise the RPM by opening the IAC.
If you adjust the settings for the throttle stop to set the idle speed with the IAC unplugged, after you are done you should unplug your battery and the spout connector for about 30 minutes to activate a learn cycle. The throttle plate should never close completely otherwise it can stick.
I solved idle hanging by reducing the idle speed with the IAC disconnected.
My current problem is surging when you let up lightly on the accelerator.
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