injector firing order wrong?

Working on a 2002 5.3. transplanted into a k5 blazer with manual transmission. PCM is service #09354896
Engine runs decent but has loss of power and sounds like a misfire. (Also misfire counter isnt working). LTFT is 18-25 on bank 1 and -3 to +3 on bank 2. Alot of testing has lead me to hooking up a noid light to the injector connector and using vcm scanner injector on/off found that disabling injector 1 actually disabled injector 8. 3 disabled 1, 5 disabled 3, 7 disabled 6, 2 disabled 5, 4 disabled 2, 6 disabled 4, and 8 disabled 7. I checked injector wiring to the PCM and its in the correct terminals to the PCM. Ive seen where others have ran across this on here but no one has posted the correction if there was one. Any ideas anyone? Ive switched the firing order in the tune but as others have stated that doesnt change what im trying to do.

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Originally Posted by camaro1

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Thanks for the schematics. I have access to Service Information as well. Wiring is correct on the injectors to PCM. I must have either the wrong PCM or wrong calibrations for that PCM. I just dont know if a new PCM such as a 0411 will solve the issue. Trying to avoid trial and error.

Our GM parts catalog (dealership catalog) shows the 09354896 PCM compatible for up to 2000 model year. But cant see how that would matter if the tune is also a 2000.

I figured out that vcm scanner wasnt turning off the injector it says it was. i borrowed a tech 2 and when turning off injector 1 it actually turned off number 1. Went all the way around the world to figure this out though. I dont know whether to blame vcm scanner or the tune. either way its solved now.

I just came across this same issue trying to diagnose a rough idle on my 2012 Sierra Denali (L9H) with E38 ecm. Disabling the injector with the scanner did not match the cylinder reporting the misfire. My results were (inj control - misfire cylinder): 1-3, 2-4, 3-5, 4-6, 5-2, 6-7, 7-8, 8-1. Although the intake manifold has been off, I am pretty certain injector wiring is placed correctly. I would be pretty hard to swap 1 & 8.

I'm going through this same thing trying to troubleshoot a dead misfire on a '04 Trailblazer. I've thrown everything at Cylinder #2 chasing this problem, since that's the one that doesn't change when I disable the fuel injector. I finally did a search on this because it's literally not misfiring.

I love having HPTuners, but god damn is this an annoying fucking issue.

Anyone figured out this cross reference on an '04 Trailblazer 5.3L?

[edit] Surprise, disabling #2 injector actually disables #4. Found it was cylinder 4 by looking at Misfire history. Ended up being a dead coil. Damn, that was a huge waste of time.

the vcm scanner controls are generic guys, they simply access the controls given within the confines of the factory system. Because all these platforms are different on a case by case basis, it would require a different scanner control for each and every system. Your expecting several thousand dollar features on a couple hundred dollar budget. This is a tuning platform, not a diagnostic platform. They give us what we need to tune, if you need diagnostics, there are specific machines for that, and they sure arent $299 for anything even remotely capable of proper two way controls, I know because i own most of the top machines

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Originally Posted by mbray01

the vcm scanner controls are generic guys, they simply access the controls given within the confines of the factory system. Because all these platforms are different on a case by case basis, it would require a different scanner control for each and every system. Your expecting several thousand dollar features on a couple hundred dollar budget. This is a tuning platform, not a diagnostic platform. They give us what we need to tune, if you need diagnostics, there are specific machines for that, and they sure arent $299 for anything even remotely capable of proper two way controls, I know because i own most of the top machines

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I hear what you are saying but why have that feature if its not going to work properly. I'm 4 hours into trying to figure out why a click of the mouse does't do what is says it does. I'm chasing an A/F ratio issue and discovered turning of an injector on the left bank leans out the right bank. I would rather not have a the feature without it giving me a warning that the injector number may not be the same as the button number.

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Originally Posted by bnewsom

i hear what you are saying but why have that feature if its not going to work properly. I'm 4 hours into trying to figure out why a click of the mouse does't do what is says it does. I'm chasing an a/f ratio issue and discovered turning of an injector on the left bank leans out the right bank. I would rather not have a the feature without it giving me a warning that the injector number may not be the same as the button number.

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the feature isnt meant to diagnose exactly what an issue is, the feature is meant to determine if there is an issue. If by turning off the injectors one by one you find one not firing, then you know you have a dead cylinder, from there its on you to determine what you need to do.

Hpt gave us a tool, a tool that works spectacularly for what it is intended for. When you start tuning, do you just throw numbers in tables, and hope it works? Or do you research what each table does, and then make changes. Its no different here. You tried using a function without finding out exactly how it functions, and now your mad because you chased your tail. You assumed something, and your assumption was wrong, that is not on hpt.

I came upon this thread for the same reasons as stated above and Michael's explanation, unfortunately, makes perfect sense. Looks like there might be quite a few of us out here blindly believing that hpt is cancelling the "indicated" cylinders. It would be nice is hpt could flag that feature with a warning. Wouldn't take much on their end and it would save a lot of us diy guys from chasing a ghost.