I'm working on an '89 Accord LX-i (fuel-injected engine), and when checking some other things, I noticed that a small device, which I believe to the Vacuum Advance for the distributer, is supposed to have two hoses attached to it, but only one hose is attached. The other hose is lying nearby and has a screw stuck in the end of it, the purpose of which appears to be to clog that hose. A picture is attached to illustrate what I found.

Clearly this isn't how it's supposed to be. Right now the car can't start due to a bad battery (and I haven't gotten a chance to jump it), but the engine did seem to run fine the last time he drove it.

Is this going to significantly degrade performance/gas mileage/emissions to leave it that way? It seems a new replacement is nearly $90 and that is a lot to pay.

Thanks in advance!