hexdmy
September 7th, 2015, 03:13 AM
I've done a bit of GM tuning, primarily on the older LS1B controllers, however I did tune a 2010 Camaro with an Edelbrock supercharger some time ago and struggled a bit with the fuel trims. It seems that I could tune it on the dyno, then go drive the car and the fueling would shift lean considerably at light load, and I would have to go though the MAF table again, using data I collected during the drive. This was a few years ago, and it was using another piece of GM tuning software. I now have EFILive, and an opportunity is coming up where I may need to tune a E67 controller on an engine swap, so I have started reviewing the tuning process again for these controllers. Interestingly, and on another forum, there have been a few threads on this "rich after flash issue", one person actually documented it on the bench using a simulator, and it appears that the ecu applies a small pulse width offset after a reflash on a hot restart of about .3ms that slowly goes away if the engine is run for about ten minutes. Another observation made by several people on that forum, is that you do a couple of hard pulls on the dyno, the offset seems to go away faster.
Looking around the EFILive forums, I don't see any mention of this issue, which is surprising because it says to me that either people using EFILive are not having the issue, or are just not observing the issue. I would say that on a stock engine, the offset is annoying by not too much of an issue, however it becomes a big issue once you install large injectors or if you are working with a heavily cammed engine which tend to be sensitive about the air fuel mixture.
So I have brought up this topic to ask these questions:
1 - are others experiencing this rich after flash issue with the E38 / E40 / E67 controllers ?
2 - if so, does anyone know what causes this issue, and can EFILive chime in on this ?
3 - again, if this is an issue using EFILive as well as other tuning suites, would it not make sense for the software company(s) to look through the GM code to find out what is going on ?
Any thoughts or suggestions are appreciated.
Looking around the EFILive forums, I don't see any mention of this issue, which is surprising because it says to me that either people using EFILive are not having the issue, or are just not observing the issue. I would say that on a stock engine, the offset is annoying by not too much of an issue, however it becomes a big issue once you install large injectors or if you are working with a heavily cammed engine which tend to be sensitive about the air fuel mixture.
So I have brought up this topic to ask these questions:
1 - are others experiencing this rich after flash issue with the E38 / E40 / E67 controllers ?
2 - if so, does anyone know what causes this issue, and can EFILive chime in on this ?
3 - again, if this is an issue using EFILive as well as other tuning suites, would it not make sense for the software company(s) to look through the GM code to find out what is going on ?
Any thoughts or suggestions are appreciated.