Howdy,
New to the forum, hope you guys can help the new guy out. <O</O
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The wife drives s a stock ’01 K1500 Suburban that has given us 140k trouble free miles. Over the past several weeks we find trouble starting first thing in the morning. If you get in, and turn the key, it cranks fine, but will not fire (sometime 10 seconds or longer). When you stop and try again, it fires right up. I do not think it ever happens during the day after being driven. My first thought was some type of fuel delivery issue, but a friend said it may be the cranks location sensor.
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I have not done much diagnosis, other than confirmed the fuel pump is engaging (can here it cycle when the key is on) and I checked fuel rail pressure first thing before the key was turned and there was none (not sure if that is normal).<O></O>
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Any thoughts?<O</O
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Thanks,<O</O

 

Welcome to the forum.

What's the fuel pressure w/ KOEO?

 

Thanks, f<O</O
I do not have that tool in the arsenal yet…(my other rig is a carbureted FJ40). I will get fuel pressure tester then report back

 

Morning,
It took a while but I got the fuel pressure tester. I ran it this morning and found the following (numbers form memory but should be close)
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KOEO spec 55-62 psi<O</O
Result 58 psi – ran several times and very consistent.<O</O
Engine running ~48-52 psi flickered slightly

HOWEVER, with KOEO, after 2 second the fuel pump stopped and pressure dropped to effectively zero in a matter of 10-15 seconds. There are no signs of exterior leaking anywhere, so per the manual this could be leaking injector (which I doubt since there is no smoke on start up) or at the fuel pump. I believe the next step for me is to repeat the KOEO test, then close both supply and return lines, if pressure still drops, then is it a leaking injector(s), if not, it is in the pump. Do I really need to install the gas shut off switches or can I just clamp the flex line off?
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Does this sound like I am on the right track?
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Thanks,

 

Does the oil smell particularly gassy? if not, then the injectors are probably not leaking...and the inconsistent pressure while running is probably the fuel pump...

 

Thanks for the reply - oil smells fine, given the evidence I am going forward with the Fuel pump change.

Thanks!

 

Last question ( I hope) any way to tell what type of fuel pump (TDC or not) without remvoing the tank first? I prefer to have the pump in hand befoe I take the tank down
Thanks,

 

Check out GM parts direct, once you find what you are looking for add it to the cart and I believe it will display the part number...
Any local auto parts store will be able to give you a selection of fuel pumps to choose from, OEM is preferred but typically will cost more. expect a price range of about $225 to $450....keep that in mind if you decide to go the less expensive route, you may be back under the vehicle to change it out again ..

 

Thanks!