Fuel injector flow rate
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Joined: Jan 2001
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From: Virginia
As you move the throttle back and forth with the engine off, it's what the throttle butterfly rests against. You should pull the large intake hoses off and open the throttle blades manually and clean the blades and the throttle body area with brake or carb cleaner. And you should also pull the idle air control valve and clean it out also. All this before adjusting the idle stop screw.
Since the starter of this thread had been working on his engine, I didn't think about his throttle body being dirty, but your comment reminded me of that. He should check how clean his throttle body and idle control valve is also.
Since the starter of this thread had been working on his engine, I didn't think about his throttle body being dirty, but your comment reminded me of that. He should check how clean his throttle body and idle control valve is also.
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Cross-Country
Joined: Mar 2015
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Likes: 6
I think the throttle body and IAC are relatively clean. After the truck stalled while at a stop I gave the idle screw a small turn in and it seems to be running quite well at the moment.
Last edited by Chasm*18; May 27, 2024 at 02:55 PM. Reason: Error
Lead Driver
Joined: Apr 2002
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I don't know about your engine, but I know that some Ford engines with EFI had issues with the throttle body butterfly gate bushings wearing out. When they get loose the idle can wander. Some Ford shops would only make the repair by swapping out the throttle body. Probably can replace the bushings yourself.
Lead Driver
Joined: Apr 2002
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The symptom is an idle that jumps around. Sometimes normal and sometimes goes high. The cause can be worn bushings which allow the butterfly to wander. Closing off air one moment then allowing air to bypass causing the idle to rise. If the butterfly wiggles around too much it can wander.
FTE Legend
Joined: Nov 2015
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From: Angier, NC
You can also spray carb cleaner, using the straw, and spray at the shaft ends to see it that makes a change.
Just be careful that the spray dose not get pulled into the TB and give you a false reading.
Dave ----
Just be careful that the spray dose not get pulled into the TB and give you a false reading.
Dave ----
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