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How to check for bad injectors without a scan tool?

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89K views 29 replies 12 participants last post by  EvilOgreLorde  
#1 · (Edited)
Ok guys I'm a long time reader and first time poster here. I did read the sticky and know how to work a search engine. I apologize if this is a dumb question but I'm not finding what I need.

So the condensed version of my story is I have a bad fuel knock and lots of black smoke (no diesel in oil). I understand there is most likely one or more injectors stuck open. Now being a broke college kid logging part time to work my way through college, I don't have the funds to buy a Tech2 or EFI right now.

Is there any way to check cylinders through glow plugs? I think I read something somewhere about pulling glow plugs and FICM fuse and turning over the engine. If that make any sense, could some one explain to me a little more detail what the proper procedure is?

Also do injectors go bad like this overnight? The injectors where checked and resealed with new lines not 2K miles ago when the head gaskets where done. The truck ran fine with no issues not 6hrs before It started knocking. I did forget to plug in the block heater that night and I had to prime it by hand to get it to start in the morning. I changed fuel filters and let it warm for the whole day. I also have been running the white Diesel Kleen in every tanks. I got balancing rates jumping to 11 on cylinders 1,2,3,7 if that means anything.

This is my first diesel truck so I'm learning as I go. I have a bit of experience wrenching on gassers and heavy diesel equipment. Sorry for the long post. Any and all info is much appreciated.
 
#30 ·
[snip] The injectors that are stuck open will still allow fuel to enter the cylinder. This fuel will spray out the glowplug hole. All this test will do is show you which injectors may be sticking. [/snip]
I know this is an OLD thread, GREAT INFO! I have been searching for fuel knock info as i think i have a hopefully fuel knock in my Kodiak. Man o man finding this thread 2 weeks ago would have been way helpful. I pulled my injectors on just to take them up to get them tested at the local fuel injection place. good info i will keep this in my back pocket for a bit. I am running LBZ, i am new diesel owner so i do not know how much of this will cross reference.