[briansansone]

What is the best way to check for vacuum leaks?

What are some ways to use a vacuum gauge to determine running condition?

I have found a crack in the upper intake of my chevy 4.3, and
I'm wondering if I could see the effects of that crack in the vacuum the engine produces.

[S10 Racer]

The best way I found to check for leaks is to spray carb cleaner around gaskets, hoses, etc. If the engine revs up, you have a leak at that point.

If your intake is cracked, yes, it can affect vacuum and make for a poor running engine.

[cobalt327]

HERE is a vacuum gauge reading guide. THIS is another one.

Spraying WD-40, etc. around suspected vacuum leaks is often recommended. You can sometimes hear a vacuum leak, though this isn't too common.

Check all the hoses and accessories, you can disconnect some of them at their source and plug the openings to se if the idle speed changes. Be careful, though- removing some vacuum lines can set a code. No biggie if it does, just making sure you're aware of the possibility.

[briansansone]

Thanks!
Just what I was looking for