I have been puzzled by that spring also.  I would think it makes the throttle a little stronger so your leg wont get tired.      If your revs stay high, I would be looking for an air leak on the engine side of the throttle body, perhaps a vacuum line that has perished.  

Steve

On May 4, 2013, at 2:37 PM, John Meeks wrote:

> That long spring that goes from the air plenum to the tab on top of
> throttle return spring doesn't seem to do much on my stock 2.1. Should the
> spring return the tab to fully counterclockwise position?
> 
> I'm trying to fix an intermittent problem where the throttle keeps the RPMs
> high with foot off the gas pedal & the clutch down or in neutral.
> 
> Every time I check it while engine is running fast, that tab is full to the
> clockwise. RPMs fall to normal when I rotate the tab to the
> counterclockwise position.
> 
> I've cleaned the throttle body and lubed the return spring. Do I need a
> shorter spring? I'd like to understand what that long spring should be
> doing.
> 
> Thanks,
> 
> John Meeks
> '91 Multivan
> Stock 2.1 250k miles
> 
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