Throttle Body/Throttle Plate Fitment

[devo]

Cleaning the intake today and noticed that my throttle plate does not seal snuggly against TB. The throttle plate is closed completely.
Is this gap an issue or insignificant?
Thanks

 

[ajax1]

I’ve never checked it with light Bob, always just made sure it was fully seated (butterfly vertical not at angle) and not being held up by gunk. I would guess normal, and change the throttle coolant lines if you haven’t.

 

[devo]

You know on an Asian carb the butterfly valves are beveled and seat tight.
It is vertical and clean. Coolant lines are fresh!

 

[OffRoadScott]

Can't fully seal off the throttle plate if so how would the engine breath at idle?

If you don't feel comfortable I am sure there is a process in the FSM that tells you how to check/adjust the set screws, the ones that stop the throttle plate from over rotating.

 

[devo]

Not really anything I could find in the FSM about the TB and adjusting the plate to reduce that gap. The plate is not over rotating and there are adjustments for the plate to come completely vertical. I’m sure it is fine. Just an observation after 305K miles.
I’m also with the understanding that at idle the air that the engine needs is metered by the IACV?

 

[ppc]

Can't fully seal off the throttle plate if so how would the engine breath at idle?

If you don't feel comfortable I am sure there is a process in the FSM that tells you how to check/adjust the set screws, the ones that stop the throttle plate from over rotating.

@devo The throttle should close completely. The engine will "breath" through the "bypass" that is modulated by the IAC valve
IAC = Idle Air Control

Solely based upon your cleaning process I would check:

Disconnect the throttle cable and make sure that is not the restriction. Seeing your picture on the workbench, off the vehicle, is not fully closing is not and is not and issue but if you get if fixed then check the cable..

The throttle plate is most likely binding because it is not completely centered. Loosen those two screws and to get movement in the plate. When it closes completely then tighten the screws.

Remove the plates to check the free rotation of the shaft.

Make sure the cable, when not connected, moves smoothly/fully and is .

 

[devo]

Yes the engine does breath through the IACV. There was no binding from cables, the TB was off the engine. The plate is not binding and is off center. I left it as is. The throttle shaft rotates smoothly.

Nothing was really wrong, it was simply an observation I made having the TB on the bench!

It’s all cleaned up now and back on the engine. While off I changed the TPS and IACV. TPS adjusted to perfection per the FSM.
The engine runs smooth and sweet with a resting idle @625.

….and down the road i go!