how important are vacuum leaks?

[bigDcruiser]

i was under the hood this weekend and found 2 vacuum hoses that were not connected. one of them looked like it went to the egr? but the "nipple" had broken off. the other i didn't find a purpose for. honestly i'm guessing b/c i don't know a hell of alot about this engine but i stuck golf tees in both the hoses and duck tape over the broken "nipple". she still idles at about 1k but the throttle response seems to be markedly better. i thought i was imagining things at first but she really seems to respond to my right foot much better. keep in mind this is a truck that could not make it from one traffic signal to the next w/o catching the red many times. i'm just wondering do vacuum leaks make that much of a difference?

 

[serenity]

they made a huge difference on my rig when i had a couple that were attached to the wrong things. it wouldn't idle at all, then i attached them all correctly and it runs beautifully.

do a search there is alot of info on having vac lines replaced or routed correctly. any leak out of a vac line will have a detrimental affect on your car.

and if you havent done it check all your vac lines for cracks or leaks and replace any that need replacing. and check that they are all correctly routed.

 

[hank14]

You'll be amazed how many things can go wrong when all the vacuum lines are not hooked up properly, or there are broken or missing fittings. I assume your cruiser is smog testing exempt in Texas now, or getting close to it, right? If so, you might consider desmogging to save a lot of headaches and some $$ if there are a lot of non functioning smog parts.

 

[bigDcruiser]

yeah, last year was the last smog test for her. i have gutted the smog pump and want to do the total de-smog but haven't had time since she's my dd.

 

[2mbb]

There is one hose on the drivers side of the engine that doesn't get connected to anything. It comes out the bottom of the HAC valve (High Altitude Compensation valve). It's just an atmospheric vent. If you plug it and go to high elevation, you may have problems with your spark advance. Do a search on HAC and you'll find some pics of the valve.

 

[bigDcruiser]

that's probably it. the second hose was on the ds and came out from the bottom. thanks.