(The following has been posted by myself in another forum, but just wanted some more feedback)

Hi guys, after being a long time lurker and reading quite a bit I have finally managed to delete/close my EGR using the two hysteresis tables method, well, almost.

A little background:

My car had a dpf delete done on it, before I took ownership. It was going to be a project to build a hardware emulator using some discrete components costing less than a pound to fool the ECU into thinking dpf pressures as expected. Long story short, i could not get the MIL light to come on with the dpf unplugged and further investigation showed the dpf had been cut and shut. So that was the end of that little project. So I decided to do an EGR delete with a stainless steel plate in front of EGR valve, but this caused the MIL every time I started the engine.

A bit of googling has taken me down the ECU remap route, and I have so far cloned my original ECU into a second hand equivalent and brought the PCB solder pads out on a ribbon cable and made them accessible in the engine bay (ECU is in the wheel arch, behind liner, inside another plastic housing! What a stupid location). I went this route as I read that any OBD writing of the Ford ecu would probably end with a "bricked" ECU.


So I flashed new (second hand) ecu with my map changes (Hysteresis maps at 1C3C68, 1C3C8A all values set to 0) and it now shows EGR_TV is constantly 1.97%.

I did use Forscan to log the EGR request before and after change and indeed it looks as though it is working, except it says it is 1.97 % open at all times. It also was never 0 in the before change, it too was 1.97% minimum and going to 10%+

I guess this is some sort of "learnt" value for the closed position, but would like someone with more knowledge than myself to confirm this, and is not in fact always slightly open.

I also noted another map at 1C3C46, which had 8x1 and filled with 128. I changed this to all 0's and again uploaded (BDM100), this time the EGR_TV started at 10+% and quickly returned to 1.97% once the car was at temperature (might be useful for improving warm uptime). Then set all the values to 256 and tried again. This time the EGR_TV started at 2.27% and then went to 1.97%, again quite quickly.

So is it possible my valve is always 1.97% open or is it more likely this is the calculated position for being closed, an offset if you like?