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Why don't diesels make vacuum?

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Old 05-14-2013, 01:29 PM
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Why don't diesels make vacuum?
Well? Why does it need an actual vacuum pump?
 
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Old 05-14-2013, 02:04 PM
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Diesel engines have no throttle plates to restrict air to create the vacuum. Speed on a diesel is controlled by how much fuel is injected into the cylinders, the intake remains unrestricted thus no vacuum is created.
 
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Old 05-14-2013, 02:04 PM
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Knew it had something to do with a throttle plate. Thanks!
 
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Old 05-15-2013, 04:09 PM
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Originally Posted by garrettsr5
Knew it had something to do with not having a throttle plate. Thanks!
Fixed it for you. There is no throttle plate.

The vacuum pump is required to run the dash HVAC and P/B, since the IDI trucks are based on gasser design truck bodies.
 
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