Idles rough and there is no vacuum at fuel regulator

2005 CHEVROLET COLORADO
265,500 MILES • 5 CYL • 2WD • AUTOMATIC
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TOMLINFIVE
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My truck idles rough. I had fuel pump checked, okay. Checked for vacuum leaks found none. It does not have vacuum at fuel regulator, replaced regulator. Still idles rough spark plugs are new.
Jul 10, 2018 at 12:05 PM
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JACOBANDNICKOLAS
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Hi and thanks for using 2CarPros.com.

I have attached a basic vacuum schematic for you to review. The first picture shows five components. Number five is the regulator. Picture two is a list of the components by number. Take a look and you will see that vacuum to the fuel pressure regulator comes direct from the throttle body. Either there is something plugging the hose, or there could be a carbon build up in the throttle body preventing vacuum from getting to the regulator.

That is the first thing I would check. Do this and let me know what you find.

Take care,
Joe
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Jul 10, 2018 at 8:06 PM