Vacuum leak found, but idle jumps...

[fastmonkeywheel]

I finally got a boost/vac gauge and found that at idle I was only pulling ~15 Hg. This probably explains my hard starting and rough idle. Anyways, I started spraying starter fluid around the intake and other vacuum hoses and got a responce from the EGR valve. Turns out I forgot to install the EGR gasket. Normally when starter fluid is sprayed at a vacuum leak souce the idle jumps, but instead it dropped. I thought this was odd and wondered what everybody else thought.

This is a 78 Mustang II with an 86 T/C motor.

 

[bhuff30]

I'd expect the idle to drop. By spraying fluid there, you are temporarly keeping the engine from taking in more air. Not only will it go suddenly rich, but it won't have the additional air supply it had coming through the leak before.