Hey all,

The guy that had it before me had it wired so that the injectors were seeing like 12 volts (or less) and the PCM was thinking it was seeing like 13.

Before the rewire, the tune was on with BLM's at 128 or close to but now I am running pig rich across the board. Running VE.

I know how to correct the situation but I am trying to understand why. I have had to go from 100% VE at WOT and 5000 RPM+ to around 75% to get the BLM's to agree on 128. This is of course with PE mode disabled and I am testing all cells.

I am guessing the injector offsets need to be adjusted but not sure. When I changed the injectors a year ago, I did not have to change the programming at all to account for the change in offset for the larger injectors. At that time, I just adjusted injector size and was good to go but back then the wiring was messed up then also.

Thanks,
Ben

 

The increase in voltage leads to an increase in current flow, basically the net result of getting more voltage to the injectors means that you get more electromotive force and they open and close quicker. This is the reason that we have injector offset vs voltage. In some cases that I have seen you can actually 'fix' blms by doing nothing more than adjusting the offset. However, I only do this when I have blms that 'shift' on me and I can see that it is happening with voltage changes like when the alternator is charging vs when it isn't and the car has been running awhile.

I hope that helps your understanding.

 

It helps me understand but not correct the issue. I tried an adjustment of reducing the inj. offsets by about 61 microseconds and there was a change but minimal. If I were to adjust the offsets, I believe I would have to reduce them by over 50% That seems pretty extreme.