Could anyone please identify this green wire for me? It snapped off while I was changing my spark plugs. I assume it's some kind of throttle sensor?

 

That is not a wire that is a vacum line going to the EGR valve you can patch it back with 5/32 rubber vacum hose.

 

No, no not the hose. If you look at the second picture it's the snapped green wire resting on the hose.

 

That's a hose man had the same happen to me on my 302

 

Damn, that thing is tiny. What does this EGR valve do? Is this causing problems?

 

Google Exhaust Gas Recirculation for an indepth discussion, but basically it is a part of the emissions system.

Not patching it back up with some plain rubber vacuum hose will cause a leak when the ECM commands the EGR controller to open sending a vacuum signal to the EGR valve itself. In addition to the leak, you'll get a check engine light when the EGR doesn't respond.

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