This looks like my '96 engine. Instead of ripping into the IAC device and having the "modification" show up on emissions inspection (which I know many places have) and making a change that would be difficult to reverse, wouldn't it be simpler to restrict or plug one of the hoses?

A 2 liter engine doesn't need a lot of air to idle. Those hoses look pretty large for controlling bypass air around the throttle body only at idle speed. A restriction would let the system bleed some air at idle but would keep it from bleeding a lot of air at higher engine speeds. Maybe the large hoses allow it to let the engine coast with a lean mixture when the throttle is lifted, which doesn't really hurt anything. Modern engines don't have a lot of engine braking for this main reason.

Hmmm ... I see an experiment here. Trying various restrictions and watching gas mileage and the output from the oxygen sensor might be revealing. It would be necessary to probe the sensor first and see what the engine does in its factory configuration before making any changes.

Don, y'all
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