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2000 GMC 7.4 454 STARTING/ FUEL PROBLEMS

Hi, i have a 2000 gmc with a 454 with 60,000 miles on it. lately i have been having starting problems. it does not occur at all times. when the truck sits over night has time to cool it starts perfectly fine but the problem occurs if i stop somewhere for about a hour or so you have to hold the ignition about 3 times as long as normal before it starts, i also noticed that when this happens flooded fuel smoke comes out of the exhaust. what believe is happening is one of the fuel injectors is stuck and the pressure bybass into the motor, or its not firing on initial startup which would explain why it starts fine in the morning over night and if i stop somewhere for 20 or 30 minutes. it give the fuel time to evaporate overnight. i am not sure what exactly is the problem. no check engine light brand new ac delco platium plugs, standard ignition cap, rotor, new wires, the intake manifold was also leaking but that is fixed now.

anyone else with similar problem any help would be appreciated!! thanks

Reply to
Steven
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Steven-I think your diagnosis is right on..I don't have alot of experience with the bigger GM's but this sounds like a similar problem that I see all the time in GM's smaller S-10 Blazers, which I deal with a ton. You'll have to put a fuel pressure gauge on it and key it on and then off. Your looking to see that it maintains the pressure that it(the gauge) showed after initial 2 second pump run. Too bad if you just did intake manifold gaskets that you weren't aware of this problem but....thats Murphy's law, right? Good luckkeep us all posted JP btw-I suspect the problem being either leaky injectors or most likely the fuel pressure regulator

Reply to
blazerman

Reply to
Steven

Steven-wonder if you or someone you know could scan it and look at the sensors-what they are reporting..Although no SES lite, if for example a coolant sensor was off in it's reporting, that could be an issue even though no check engine lite. Also, at this point, I tend to agree with you that the pressure seems fine. A fuel filter wasn't mentioned as being previously replaced but as you say when it starts it seems rich-I tend not to lean that way. Scan and look at sensors- just a thought. jp

Reply to
blazerman

Reply to
Steven

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