rough idle and its killing my paycheck with gas bill

18,800 MILES
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BIGB50MM
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I have a 98 5.7 vortec it has rough idle mostly when ur at a redlight in drive blows out black smoke when u get on it strong running rich smell
Jun 24, 2012 at 5:13 PM
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RASMATAZ
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-Possibilities for running too rich:

1.Excessive fuel pressure can be cause by restricted fuel return line

2.Defective Oxygen Sensors.

3.Leaking injectors and fuel pressure regulator.

4.Coolant temperature sensor out of calibration.

5.Restricted air intake system.
Jun 24, 2012 at 5:32 PM
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BIGB50MM
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Wow ok a mechanic changed the head gaskets because one blew the heads wete checked and there not cracked it never did it until they fixed the gasket
Jun 24, 2012 at 5:44 PM
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RASMATAZ
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  • 75,988 POSTS
Might want to refer to this link for more information: https://www.2carpros.com/articles/engine-black-smoke
Jun 26, 2012 at 6:09 PM
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