2000 GMC Sierra starting problems

2000 GMC SIERRA
115,000 MILES • V8 • 4WD • AUTOMATIC
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KECRUZ
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I have a 2000 GMC Sierra 1500 4x4 that is hard to start. It starts fine when it's cold out or the first start of the day. If I turn it off after it's been running and let it sit for a while I have to crank the starter two or three times before it starts.When it start it starts rich and black smoke comes out of the tail pipe. I have replaced the fuel pump,filter and spark plugs I''ve also had to replace the crank senser.Can you help please.
Dec 23, 2007 at 10:59 PM
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SERVICE WRITER
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Probably a crank sensor that is being affected by the heat. You may be able to get it to act when cold by hitting it with a hair dryer when it's cold.
Dec 23, 2007 at 11:30 PM
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KECRUZ
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I changed the crank sensor about 8 months ago. do think it is going bad?If I let it run and turn it off and start it up within say 2 to 3 mintues it well fire right up regardless of the ambient temp. But if I let it set for 5 to 10 minutes it takes two some times three crank before it crank over regardless of ambient temp.
Dec 24, 2007 at 12:37 AM
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SERVICE WRITER
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Straight forward, I don't know the cause. But I would try the heat like i suggested to start with. Seems like these have been a problem from my experience. It costs nothing to try. If not we go forward from there.
Dec 24, 2007 at 1:06 AM
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KECRUZ
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I tried the hair drier and no change. I would appreciate anyother suggestions thank you..
Dec 26, 2007 at 12:22 PM
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SERVICE WRITER
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Is that a 5.3 motor? Have you checked the fuel pressure when the problem was happening? IF it is the 5.3, be aware these had a problem with the fuel pressure regulator.

Also did you change the connector at the fuel pump when you replaced the pump?
Dec 26, 2007 at 6:23 PM
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KECRUZ
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Would my check engine light come on if I had a bad sensor? And yes I do have a 5.3 in it.
Jan 16, 2008 at 7:26 PM
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RSSSCA68
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mine did the same thing. i replaced the fuel pressure regulator and its fixed.
Aug 1, 2020 at 8:30 PM
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JACOBANDNICKOLAS
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Thank you for letting us know. I am sure it will help others in the future.

Take care,
Joe
Aug 2, 2020 at 12:39 AM
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