Chevy lumana 96 won't stay running unless i give it gas, and my breaks are very hard to press?
Either the brake booster has a hole in its diaphragm or the line going to it is destroyed. An easy way to find out which one it is, would be to pinch the vacuum line going into the booster and see if it clears up. If it clears up then its the booster, if it still runs like crap then its the line. I have only personally seen one booster that went bad. On the other hand the vacuum line is made of rubber and I have seen those go bad thousands of times. I'm also quite positive that as soon as you locate the line you will immediately see its bad. Take a chunk of it into the local parts store and get a hunk of heater hose to replace it.
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