Good day,
No, haven't given up already. I made a mounting board for all the prototyping parts for easy storage and transport, but haven't finished attaching everything just yet. It has a terminal strip for adding larger connections, fuse holder, 2 breadboards for smaller components, the throttle body itself, and eventually my PIC programmer. Have a relay on hand to simulate controlling the fuel pump also, but haven't wired it up. Hit a slight hiccup with my programmer, as the older ICD2 doesn't support the correct lower programming voltage for my chosen chip. I've played dirty pool and just used a voltage divider previously, but couldn't get that to work with the 18F46K60 so far. Adapter is on hand now, although I haven't tried it out. One new picture on Flickr of the prototyping bench setup if anyone cares.

On the programming side I have a basic framework in place. So far the chip cycles through the various analog input channels, starts the sample, and stores the value once measurement is complete. Currently the plan is for the TPS input voltage and RPM input voltage to primarily control the fuel injected by interpolating in a 10x10 or 12x12 array of injector on durations. Other channels are primarily used to modify this process, for example, on time is bumped up when measured intake air or coolant temps are cold.

Fairly soon in development I'd like to get a serial port working so measured values can be transmitted to a laptop in real time, and perhaps some rudimentary commands can be given to the chip also. Laptop side might be handled in Hyperterminal or LabVIEW if I'm feeling ambitious.

Happy New Year to everyone on the board.
Have fun,
Mark