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Black smoke and vac line


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Just put new fuel pump in my truck I now have dark black smoke coming from exhaust, never had this before. What is this indicative of with these trucks?

Secondly next to the new fuel hoses I just put on at fuel tank there is a vacuum line. It runs to the rail and joins a metal 

Iine. The end near the hoses is sheared off and I have no idea what it is supposed to attach to. Any ideas?

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White smoke= Water, coolant (head gasket, cracked head)

Gray smoke= Oil (bad piston rings, valve guides)

Black smoke= Unburned fuel (choke stuck on, carb vehicles)

 

You might have a fuel injector stuck open dumping fuel.  Or a bad plug letting raw fuel enter the exhaust.  Bad O2 sensor?

 

Not sure on the vacuum hose.  Maybe a picture would help.

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Not 100% on what you’re referring to with the vacuum line. The one going to the fuel rail is for the fuel pressure regulator, the other end goes to the intake manifold.

There are also evap lines going from the rollover valves on top of the fuel tank that should then go to the charcoal canister under the hood. 

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