Head light switching hissing

I just installed a new head light switch because the dimmer for the dash lights were bad. Now I hear a hissing noise from the switch. what is it? 

Most likely, one of the vacuum lines you placed on the switch got bumped and is not seated properly.  The sound is vacuum from one of the lines.  Are your lights still going up and down at the same rate as before the switch change?

Also, you might have bumped the lockout (pull down knob under steering column) and dislodged the hose from that.

I'd check those two first.

I think it is coming from the switch. light was not working before switch so I am working on them I will check hose

Frank;

The easy way to check this would be to pull the hose off the switch and plug it with a screw or wooden dowel, then start the car and see if you still hear the hissing.

Did you buy the switch off ebay or from one of the supply houses?  The reason I ask is that Ecklers, Mid America and the others out there are very good to replace any bad parts, ebay, not so much.

Good luck!

I got it from ebay. When the light are not pulled out there is no hissing. You hear it when you pull the lights switch out. When you push it in it stops

It sounds like the switch to me.  If you got it recently, you might contact the seller and let him know. 

Alternatively, if he is not responsive, you can go back thru ebay and report it if it was advertised as new or working.

Either the switch or there's a snake in yer dashboard!!!  Try switching the lines....

My headlight switch also makes a "leaking air" noise when I have my headlights open and on. I figured it's a vacuum leak in the switch but I haven't got around to tearing my column down and the headlights still work so

I'd make sure all of the vac. limes are connected properly before condemning the switch. There have been reports of several "new" switches that were no good, but I'd still be sure it wasn't a line loose first.
As I always say..."New" don't mean squat!

you guys are so awsume!  Luke if you were a woman I would kiss you. I swith the lines on the light switch and it stoped and lights work, thanks a lot