Switching back to z31 MAF after doing z32 MAF mods

[enjoyrth]

I was running a z32 MAF and had all of the mods done for it. It recently took a crap on me, so I wanted to switch back to my z31 maf. I have an 86 ECU in my 88 300zx. When I put the z31 MAF in and switch the VQ tables in nistune, at an idle I am pulling much more than the 1.15V or so I was pulling with the z32 maf. I thought this was normal for the z31 MAF, but when I look at my fuel or timing table, the TP tracer has me way over into the high load area, which makes my car run like crap and not idle unless I keep the throttle wide open. Anyone have any idea what I should do here?

[Matt]

Remove all the hardware mods done to the ECU which made it run with Z32 AFM for starters

You will need to revert your K constant back to factory (see one of the factory ROM images). For the 1988 VG30ET it is 607 (0x025F) for K constant

Then if you have different injectors you will need to do the injector resize to get K adjusted for those. But dont enable the rescaling since that has already been done (untick both boxes in the resize injector dialog window)

[enjoyrth]

So in order for this to work, the modifications that were done to the ECU need to be undone?

[Matt]

Definately!

[enjoyrth]

Do you mean just the zener diode addition, or all of the modifications needed for the 86 ECU.

[Matt]

remove the zener diode, the wire installed between the AFM input and opamp output

Then and solder tin wires from the pads on the ECU to the pads on the small board where the clips were originally removed