My engine stalls at idle why?

1993 CHEVROLET SILVERADO
230,000 MILES • 5.7L • V8 • 2WD • AUTOMATIC
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JACOBANDNICKOLAS
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HAve you checked for vacuum leaks? Has the check engine light come on?
Feb 18, 2021 at 1:01 PM (Merged)
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JGEASLEY
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I am going to do a thorough check for vacuum leaks this weekend, but no the engine light has not came on.
Feb 18, 2021 at 1:01 PM (Merged)
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JACOBANDNICKOLAS
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Let me know what you find.

Joe
Feb 18, 2021 at 1:01 PM (Merged)
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JGEASLEY
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ok I am really stumped now if I take the vacuum hose off my brake power booster my truck idles and runs fine except no power brakes.
Feb 18, 2021 at 1:01 PM (Merged)
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JACOBANDNICKOLAS
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Okay, if it runs good with that disconnected, then the engine is running too rich. The extra air you get is helping smooth it out.

Have you checked fuel pump pressure? I'm wondering if you are getting too much pressure to the injector or if the temp sensor is bad.

The temp sensor tells the computer the ambient temp and the coolant temp. From that, the computer determines how rich or lean to make the fuel mixture. If the sensor tells the computer it's -40 degrees, it will dump fuel for the engine to run.

Also, did you check to make sure the catylatic converter is plugged?

Let me know.
Joe
Feb 18, 2021 at 1:01 PM (Merged)
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JGEASLEY
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Where is the temp sensor?
Feb 18, 2021 at 1:01 PM (Merged)
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JACOBANDNICKOLAS
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It should be near the thermostat housing in the intake.
Feb 18, 2021 at 1:01 PM (Merged)