Bruno2 Posted December 12, 2022 Author Share Posted December 12, 2022 Actually there is an EEC-IV analyzer and a tester out there that I sent one and had the second one shipped directly to Gary. I ordered a cheap NOID light set . I guess I am going to rock the crank with the dizzy cap off today to see how that looks. My neighbor had a brick with a bad ecm. It was causing the cylinders to load up with fuel so bad.it would hydrolock the motor. I am not sure if the NOID will tell off on this or not? Link to comment Share on other sites More sharing options...
Bruno2 Posted December 12, 2022 Author Share Posted December 12, 2022 No codes is sort of making me think pcm/ecm... Link to comment Share on other sites More sharing options...
Gary Lewis Posted December 12, 2022 Share Posted December 12, 2022 No codes is sort of making me think pcm/ecm... I'm not sure if the NOID will let you tell if it is keeping all of the injectors open too long, but at least you should be able to tell if one of them is quite different from the others. And a bad ECM could cause a serious problem. Not sure how best to test that though... Link to comment Share on other sites More sharing options...
85lebaront2 Posted December 12, 2022 Share Posted December 12, 2022 No codes is sort of making me think pcm/ecm... Ok, first item, the injectors on the bank fired trucks are grouped 1 - end 4 (1458) 2 - center 4 (2367). Second item, if there is a dead short on either of the injector control circuits, then the injectors on that bank (1 or 2) will open immediately when the key is turned on flooding those 4 cylinders. If you pull some plugs and see either the end or center ones are extremely rich, I would suspect an ECM issue. Link to comment Share on other sites More sharing options...
mat in tn Posted December 13, 2022 Share Posted December 13, 2022 Ok, first item, the injectors on the bank fired trucks are grouped 1 - end 4 (1458) 2 - center 4 (2367). Second item, if there is a dead short on either of the injector control circuits, then the injectors on that bank (1 or 2) will open immediately when the key is turned on flooding those 4 cylinders. If you pull some plugs and see either the end or center ones are extremely rich, I would suspect an ECM issue. basically the ecu in bank fire efi only has two driver circuits so the ecu only knows two commands for fuel. when it triggers, it triggers four injectors at a time and does not have the ability to only do one at a time. that system came later. meaning if the problem is from the ecu then the result will show up in four or eight cylinders not just one ,two, or three. it is very possible for it to be an individual injector and not be from the ecu. narrowing it down to which cyl has wet fuel or how many can help get a direction to look. Link to comment Share on other sites More sharing options...
Bruno2 Posted December 13, 2022 Author Share Posted December 13, 2022 basically the ecu in bank fire efi only has two driver circuits so the ecu only knows two commands for fuel. when it triggers, it triggers four injectors at a time and does not have the ability to only do one at a time. that system came later. meaning if the problem is from the ecu then the result will show up in four or eight cylinders not just one ,two, or three. it is very possible for it to be an individual injector and not be from the ecu. narrowing it down to which cyl has wet fuel or how many can help get a direction to look. Mat, here is an observation about the fuel pressure test. It seemed as though I really had to get hard on the throttle to het the psi to come up. Like almost WO to get it to climb. Is that normal or is something causing parasitic fuel draw robbing the rail of the ability to pressure up? Link to comment Share on other sites More sharing options...
85lebaront2 Posted December 13, 2022 Share Posted December 13, 2022 basically the ecu in bank fire efi only has two driver circuits so the ecu only knows two commands for fuel. when it triggers, it triggers four injectors at a time and does not have the ability to only do one at a time. that system came later. meaning if the problem is from the ecu then the result will show up in four or eight cylinders not just one ,two, or three. it is very possible for it to be an individual injector and not be from the ecu. narrowing it down to which cyl has wet fuel or how many can help get a direction to look. That is exactly what I said, I even specified the cylinder numbers. Link to comment Share on other sites More sharing options...
mat in tn Posted December 13, 2022 Share Posted December 13, 2022 That is exactly what I said, I even specified the cylinder numbers. I know. certainly not correcting anyone. just saying the same thing from a different direction. I guess I'm still thinking as if I'm talking to my grown children. haha. I have to tell each one in practically their own entitled language. kids these days. anyway, I'm not talking down to anyone here. I have nothing but respect especially for the group I have been learning from. Link to comment Share on other sites More sharing options...
mat in tn Posted December 13, 2022 Share Posted December 13, 2022 Mat, here is an observation about the fuel pressure test. It seemed as though I really had to get hard on the throttle to het the psi to come up. Like almost WO to get it to climb. Is that normal or is something causing parasitic fuel draw robbing the rail of the ability to pressure up? I'm not saying that you have any certain issue just that there are many possibilities and there are a few things to check. just as many have said. the fuel is at least a symptom. it "seems " to load up or flood out. when you feel as if you are against a wall. take a break. start by checking each plug and maybe keep a note pad of findings. if you have "a" wet/fouled plug then that is a tip. if you have four then that is a very specific clue. if those four are all one bank/batch then it is possibly the ecu/wiring as was earlier suggested. if not, then look at an individual injector at that cylinder. one check to do. turn the key to the on position and see what pressure you get. turn the key off and see what you retain. if it drops with any noticeable rate back to zero then some internal leak exists. the systems do lose a little pressure over time and that is why the ecu triggers the fuel pump relay for 2-3 seconds each time the key is turned to the on position to repressurize the rail before timing out until the ecu registers a running engine. in an extreme case of a leak you would see the gauge pressure return to zero very quickly in which case you should be able to find a dripping wet plug very easily Link to comment Share on other sites More sharing options...
Bruno2 Posted December 16, 2022 Author Share Posted December 16, 2022 May have it nailed down. Pulled the ECM and cracked it open. The big blue capacitors appear burned and looks like the oil has escaped. One of them has a broken leg too. Ordered a new one and some plugs because I am sure they're are caked with soot. Also, it was radiator time. We will know in about a week if this cures.it. Link to comment Share on other sites More sharing options...
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