1991 Chevrolet Silverado Idle problems

1991 CHEVROLET SILVERADO
5.7L • V8
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BABE THE BLUE OX
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Ive got a 91 silverado 350 with some idle problems. When you first start it u need to give it throttle for a few seconds to keep er running and when she does stay running she idles really low, then if your not giving her gas and you cut the wheel shell cut out. Any ideas? Its got a new power steering pump and a nee belt new battery too im not sure if that would make any difference. Any suggestions as to what i can do would be greatly appreciated!
Jul 17, 2015 at 4:14 PM
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JACOBANDNICKOLAS
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Have you checked for engine vacuum leaks? Have you checked the idle air control valve (IAC)? The IAC is responsible for maintaining engine idle speed.
Jul 17, 2015 at 8:40 PM
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BABE THE BLUE OX
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Ill have to check those out when i get the time, new to carb motors so im just looking for some starting points
Jul 18, 2015 at 9:26 AM
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JACOBANDNICKOLAS
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A 91 shouldn't have a carb. Are you sure?
Jul 19, 2015 at 6:03 PM
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BABE THE BLUE OX
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Quite sure got a great big air filter circle air filter on top the motor.
Jul 19, 2015 at 6:06 PM
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BABE THE BLUE OX
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Only had the truck a couple days so i dont know a whole lot about it, ill send ya a picture in a hour or so when i get home
Jul 19, 2015 at 6:10 PM
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JACOBANDNICKOLAS
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I'll look for the pic. Chances are you have throttle body injection, which can look like a carb and have the round air filter housing.
Jul 19, 2015 at 6:11 PM
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JACOBANDNICKOLAS
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I attached a pic of the TBI system on a 91 GM 5.7L. Let me know if this is what you have.
Image (Click to enlarge)
Attached Media
Jul 19, 2015 at 6:13 PM
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BABE THE BLUE OX
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Yeah i would say thats what it is, like i said ive never had a carburated motor before so its beyond my knowledge.
Jul 19, 2015 at 6:14 PM
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BABE THE BLUE OX
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Thats right under the filter right?
Jul 19, 2015 at 6:15 PM
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JACOBANDNICKOLAS
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Yes, it's under the air filter housing. The two ports have injectors above them which spray fuel into the intake. This design is know as Throttle Body Injection (TBI).
Jul 19, 2015 at 6:22 PM