Vacuum/EVAP Leak

[mopar426]

What’s the difference between a Vacuum Leak and an EVAP Leak?

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[Rick]

A vacuum leak is a leak of engine vacuum which can be at a vacuum hose (like the one that goes to the brake booster or other vacuum actuated accessories like a cruise control servo). An EVAP leak is a leak in the Evaporative Emissions System which collects vapors from the fuel tank and injects them at the engine intake to be burned. Basically the fuel tank, all the hoses and other components of the Evaporative Emissions System must be sealed or the computer will set an EVAP code.

[johnzcarz]

And an engine vacuum leak will probably be there all the time but the Evap system leaks may only show up when that part of the system is doing something (which is to say it may be intermittent).

[mopar426]

Thanks…Was checking oil/fluids and felt air coming up out of the hood near one of the intake manifold runners

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