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2003 GMC Sierra 1500 Question: My GMC truck won't start. It is turns over but won't start.

 

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Maji, Madison, AL, December 31, 2012, 09:21
 Rookie

I changed ignition coil and ICM, but did not help. (I have gas in it). what is the most likely issue for my next step? Distributor?

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  • Answer #1

    Tomiko December 31, 2012, 11:11
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     Journeyman

    maybe it has low fuel pressure?

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    Maji, December 31, 2012, 15:10
     Rookie

    How can I check the pressure? Is it possible to remedy the fuel pressure issue short of replacing the fuel pump?

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    pushrod, January 01, 2013, 20:06
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     Master

    Turn key on and let the ding dong quit, turn key to bump the starter for just a second and let off but leave key on, listen closely for a click from the pump relay. May need to remove the cover on the fuse/relay box under hood to hear better.Bump starter again and again listen each time for the relay click about 3 seconds after letting off key. IF relay clicks replace fuel pump module!! BEST way to do this is to remove truck bed, if bed is empty and no tool box ect. 4 bolts on each side and unplug ALL light connectors at rear bumper, unbolt filler neck, get 3 pals. to help set bed back about 2 feet to expose pump module just behind cab. I have done a bunch of them and this is the BEST way to do the repair! Once pump module is installed start truck and check for leaks and fuel gauge operation. THEN replace the bed.
    Just take your time and watch what you are doing and you won't have any problems, Be sure to lift bed to clear rear bumper, empty bed is not heavy at all. Or call a tow truck and get a repair shop to do this for you! Good luck.
    When one of these vehicles comes to the shop on a hook, I install a fuel pump assem. then see what else may be wrong. Well it is almost that common! DON'T FORGET TO REPLACE THE FUEL FILTER!!

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    Maji, January 02, 2013, 21:35
     Rookie

    Thanks a lot buddy. It all makes sense. I did find some video on the youtube where one guy raised the cab and another guy jacked up the truck and dropped the tank. I have to agree with you, raising the cab looked much better choice. I will work on it this weekend and let you know. Thanks again for your help. Appreciate it.

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    pushrod, January 02, 2013, 21:59
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     Master

    Not the cab but the BED! Pump is behind the cab under the BED. The best thing for you to do is to follow my instructions, done been there!!! Thanks for the reply let us know how you make out.

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  • Answer #2

    PARTS GUY December 31, 2012, 11:28
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     Master

    You need at least three things for it to start. Verify spark, verify fuel pressure and volume with a gage and air.

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  • Answer #3

    pushrod January 01, 2013, 10:10
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     Master

    Very helpful to know what engine you got but i can guess at it, must be the 4.3. Since you mentioned distributor. IF you have good spark at the plug it must be a fuel problem.
    Can you ever hear the in tank pump run? When key is turned on or bumping the starter and wait a second to see if it is running.
    Pressure gauge needed to check pump psi. at scharder valve behind the throttle body.

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    Maji, January 01, 2013, 15:01
     Rookie

    No pump running. Looks like I got to replace the pump. Thanks again.

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    PARTS GUY, January 01, 2013, 16:36
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     Master

    Just because you don't hear the pump isn't an absolute that you should replace the pump.

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    pushrod, January 02, 2013, 03:59
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     Master

    After all this, you think we will ever know the results? I bet not! Seems pointless at times. I mean we don't know if these folks can figure out a forked stick or even use a screwdriver. Sometimes i feel like just saying take it to the repair shop and get it fixed rather than offer any suggestions. No useful info. most of the time, lucky to get the make and year correct! Then we can guess at the rest!!!!
    But it is entertaining at times.

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    PARTS GUY, January 02, 2013, 10:46
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     Master

    BA I used to let it get to me. What used to get to me is the top 10. People like you, me and Greg should always be in the top three. As you know the expert level is based on a points system not actual experience. So people that give lame answers with no substance work their way to the top(tomiko). I don't let it bother me anymore. All I know is that you, me and Greg are truly helping people. Isn't that what it's all about. That's why I give an email address for people that really want help. Of course the entertainment level is great sometimes.What also pisses me off is that when I went to school they really taught english. RepairPal really needs to have SPELL CHECK!
    GO REDSKINS!!!!!!!!!!

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    pushrod, January 02, 2013, 15:48
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     Master

    I dont know, i think everybody has something to contribute, not really a competition just trying to help folks out.

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    PARTS GUY, January 02, 2013, 16:42
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     Master

    I'm not talking about competition I'm talking about competence

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    pushrod, January 02, 2013, 21:17
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     Master

    Update, now that i have read a bit, i am inclined to agree!!!

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