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I am trying to figure out if the AFM on my 85 GTV6 has been "adjusted" somewhere along the way in its life.

Below is a picture of it. Notice the little door is ajar (as marked by the red bracket)…I'd say a good 1/2 inch. Is that normal? Shouldn't it be closed when the car is turned off?
 

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Nope.....................
 

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But Mad North-Northwest
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It should be closed looking in the inlet side. But I think you're looking at the outlet there.
 

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I agree. I've got a couple of spare AFM's on the shelf. I just checked & they both look like the picture posted above. If you reach in, move the flap then release it you will hear it close with gentle thunk.

The AFM's flap is like two doors connected at a right angle. As the air enters the AFM the 'door' you see as slightly open moves into a closed semi-circular space. I think this is designed to help balance the actual metering 'door'.

See the sketch on this page: AFM adjust. You're looking where the #2 is located.

 

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I am trying to figure out if the AFM on my 85 GTV6 has been "adjusted" somewhere along the way in its life.
Two clues to look for. 1) is the glue line for the black plastic cover a small, neat bead? Usually if removed by a PO it'd be glued on with RTV and be sort of irregular &/or smeared. And B), with any luck, if the PO did fiddle with the AFM's spring tension, they might have made a mark to indicate the original position. Maybe.
 

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Discussion Starter #6
Yep, it has a nice neat glue line, although I partly expected there would no glue line at all if it was done at the factory. Sounds like even the factory used glue to hold the cover on, though.

And it does look like your diagram…and thanks for passing that along. I couldn't seem to find one in all the various docs that I have.

Looks like it is stock and unadjusted…one more thing I can check off my troubleshooting list.

Thanks all.
 

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The first clue to tampering (or adjustment) would be the absence of the Idle CO plug. The 2nd might be a different kind of RTV used to secure the cover. If it's hard and a sort of light tan (and not sloppy) than it's most likely stock. But just because the cover has been removed doesn't mean the spring tension has been changed, it could be (like in my case) that the fuel pump switch has been jury rigged to stay on (which I have reversed). In any case the most common "mod" was to loosen the spring tension with the thought that this would act like having bigger acceleration jets. So one would have to check against a known stock unit because it's hard to find the spec on the correct spring tension. So you can stick your hand in there and "feel" how much tension there is. Also you can check for any binding. A few clicks of unwinding of the spring should be noticeable. Or I suppose one could use a fish scale.
AFM Comparo.JPG
So here you can a stock 2.5L unit on the right and a larger one on the left. Both have the "door ajar" look from this end. BTW the bigger unit has a softer spring tension due to larger area or "throat".
 
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