LB7: It's all over

KEVINL

Well-known member
Jul 4, 2008
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I pulled it back out and the schrader valve moves in and out real easy.


Also what is the fuse I need to pull I pulled one and I think it may still be injecting fuel the adapter was kind of black when I pulled it back out

Also I got someone to crank while I watched it goes up to 200 and comes right back down
 
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KEVINL

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Jul 4, 2008
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okay here are the numbers


360
345
370
370
370
360
365
375


Based on that I think I for sure have a bad injector
 
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ripmf666

Active member
Sep 20, 2006
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Not sure but i think I posted the Gm specs for doing this before, I will look again soon if its not there I will add it, It also gives the numbers it should be close to be.
 

ripmf666

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Sep 20, 2006
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Would be nice then you could look inside for look see,Have you tried turning the injectors on and off with efi live to see if the truck misses more or less.
 

KEVINL

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Jul 4, 2008
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In Efi Live use the Scan Tool and connect to the truck while its running and select DVT area and then you will find it there.

So would I shut off the injectors one at a time and drive it and when the smoke stops that would be the bad injector
 

ripmf666

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Sep 20, 2006
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you turn 1 off at a time while parked, as you turn them off you will fill a miss or you will not notice anything at all, when you notice no change im sure that would be the one that is bad, Someone else might chime in on this.
 

KEVINL

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Jul 4, 2008
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Yeah it might be kind of tough at idle it does idle slightly rough but does not smoke at idle.



When I changed the pressure to 160 mpa it idled like crap and smoked like crazy. But it held rail pressure. Would the smoke and poor idle point to a leaking injector?
 

durallymax

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Apr 26, 2008
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Under The Hood
YOu compression test looks good.

Turning off the injectors will tlel you right away. this is how I found my really bent rod. Mine smoked like crazy, then when i shut off #2 it cleaned up and ran perfect. Then shut off #3 and i think a pulling tractor idles better and cleaner.

At idle you should feel it smooth out some and clean up when you shut one off. you can rev it up some too and this will help.

Now it aint gonna be really smooth because your only firing 7 cylinders but it should still help.