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Hello,

Last night I took out the vacuum guage to get some readings and I removed a rubber cap from a connection port on the base to connect the vacuun guage.

Anyways, when I removed the rubber cap the engine RPM's climbed much higher. I thought that if I removed a cap from a carburetor port the engine idle would be crappy and just on the verge of stalling.

Why did my RPM's climb? I almost wanted to drive it around the block and see how it ran.

Is this good, bad or normal? ::

Thanks Greg.
 

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That's normal, a small vacuum leak will make the rpm's rise. A large vacuum leak will make the engine run rough or stall. Don't drive it that way it won't help and the engine will be running lean.
 

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If your RPMs went up, then your car is running rich. If you removed the cap and the RPMs went down, you are running either at stoic or lean normalling and are definitely running lean with the cap off.

I would check your carb and timing since it sounds like you are running rich. That's not necessarily a bad thing. It only means you are wasting fuel and maybe robbing a little bit of power.

Slade
 

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Thats not always the case. My demon can run a small vaccum leak but wont take anymore fuel. If i try to lean it out it will start to die if there wasn't a leak.
 
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