Assign injectors to different cylinders?

[tictakman]

I have a running issue with my ls and I was trying to troubleshoot a slight hesitation or miss that I can hear when I rev the car. It's a standalone harness and then a 0411 Ecu. I hooked up hptuners scanner and tried to disable injectors one at a time but I have found that they don't correspond to the the cylinder number.

C1 is injector 8, C2 is I5, C3 is I1, C4 is I2, C5 is I3, C6 is I4, C7 is I6, and C8 is I7...... Basically when I disconnected the cylinder 1 injector clip I had to disable injector 8 on hptuners scanner for it to actually turn off. I have a little noid light that I use to watch each injector turn off one at a time.

I then checked continuity from the injector wire to the correct Ecu pin and they are correct. Injector 1 goes to injector control 1 and so on...

I'm not really sure what else to check at this point. Can I change the injector assignment in hptuners or does anyone have any idea what might be going on?


Zak

[tictakman]

Nothin?

[jamesbtri]

Hey my man. More often then not posting a log and the tune will help . The ( Top tier guy's ) like to know what the are looking at . I am sure someone will hop on that !

[cobaltssoverbooster]

if you have double checked the disable with the correct firing order diagram and this is 100% the issue then under the Engine>General section there is a table in the p01 ecu's that is labeled firing order. Make sure your in advanced view or you cant see all the tables in the file.
your other option is to physically re-pin the harness preferably at the ecu connector.

[tictakman]

Hey James, thanks for the suggestion but I dont know how I would be able to actually record this on a scanner... Im physically checking the injector clip when I unplug and then disable it on the computer scanner

Cobalt, I did check the firing order before to see if that correlated and it doesnt.

Trying to explain it better...



When I disable injector 1 ( should correspond to cylinder 1, right?) on the hptuners scanner, it actually turns off the injector for cylinder 3.... I dont have any injectors that correspond to the actual cylinder. I wasnt sure if it can be reassigned or not.

I then checked the continuity between cylinder 1 injector location and ecu 1 injector control and its correct, each cylinder checks out ok.


Here is a pic of the injectors that correspond to injector on scanner.


IMG_7917.JPG

[cobaltssoverbooster]

ok if the ports match their proper locations and all your having is a scanner issue then i would report that to hptuners directly. as of now their is no way of changing disable cylinder locations in just the scanner alone.

[tictakman]

Thats a good suggestion, guess I wanted to make sure I wasnt missing something. Im going to try another ecu as well.

[jefost8]

Thats a good suggestion, guess I wanted to make sure I wasnt missing something. Im going to try another ecu as well.

Did you ever figure this one out? I have the exact same problem.

[Turbine822]

Same, whats the status on this, I currently am having STLT Fuel trim issues, one o2 that fouls out constantly. Comparing HP Tuners INJ#, IF you ASSUME that number corresponds to CYL number then INJ/CYL 1,2,3,4 Affect the correct bank o2, CYL/INJ # 5,6,7,8 affect the what you would assume is the opposite bank.

Firing order in advanced View is correct, but my chart does look odd. Firing order.JPG

Current Tune

Cylinder#/Injector# Injector# is the number from in Scanner using the disable function.
1/8
2/5
3/1
4/2
5/3
6/4
7/6
8/7

anyone got any ideas? or do I just repin the harness so the Injector # match the Cylinder #s?

-Chris

[kastein]

Same, whats the status on this, I currently am having STLT Fuel trim issues, one o2 that fouls out constantly. Comparing HP Tuners INJ#, IF you ASSUME that number corresponds to CYL number then INJ/CYL 1,2,3,4 Affect the correct bank o2, CYL/INJ # 5,6,7,8 affect the what you would assume is the opposite bank.

Firing order in advanced View is correct, but my chart does look odd. Firing order.JPG

Current Tune

Cylinder#/Injector# Injector# is the number from in Scanner using the disable function.
1/8
2/5
3/1
4/2
5/3
6/4
7/6
8/7

anyone got any ideas? or do I just repin the harness so the Injector # match the Cylinder #s?

-Chris

I know this is an old thread... bumping it to add some stuff.
I would not repin the harness just to make the utility dialog buttons match reality, that seems like overkill especially as you would have to change your tune (though you could, it's under Engine->General->Engine->Firing Order in the navigator pane, mine is set to 18726543 first through last, which is factory)

Note, it appears that this wacky button mapping is because:
Cylinder firing order is 18726543 on LS
If you apply your cylinder to injector mapping above, you get:
87654321

My guess is that the injectors and ignition coils on the LS ECU are driven by an 8 bit register each in the actual hardware, and the "cylinder numbers" in the "Controls and Special Functions" dialog are actually bit numbers within those registers, which are being turned into a bit mask that gets set in the ECU memory map somewhere to disable the injectors. So the "injector numbers" were what the programmer thought made sense looking at the bitfield in the hardware control register, not what the actual user cares about. I was really confused by this until I found your thread, but now that I have used your cylinder mapping and looked at it, it makes perfect sense as an embedded systems engineer. I just wish that this was either described in the UI on that tab, or that the cylinder firing order from the tune was used by VCM Scanner to map the injector numbers in hardware to what the injector number text on the buttons should be. I would guess it wouldn't be too hard to change that, but I don't get to look at the HPT codebase, sadly.

[anniversaryss]

Its suppose to go by firing order

[VT_Redneck]

I am having the same problem. I disable CY 4 and CY5 starts misfiring.