Bosch Throttle Body Health Check

I created a gadget that can perform a health check on the throttle bodies in our cars. This checker covers any Bosch part number 0 280 750 xxx.

Things that I've checked:

Potentiometer variances.
Two potentiometers with the primary going from low volts to high volts is checked against another potentiometer going from high to low volts as the throttle plate moves. These two readings should agree to within (I believe) 200mV. I'm checking for a 50mV variance.

Lag.
The lag from zero to full throttle indicates the health of the motor. The older the motor, the slower the response and consequently, the higher the amperage drawn from the ECU.

Amp draw.
The ECU controls and powers the throttle bodies. If the power required to turn the throttle body motor exceeds the ability of the ECU to supply it, the ECU can literally melt (as per 360Trev), and be destroyed by pulling too many amps. Knowing how much power is being drawn can indicate a failing throttle body.

Failing gears.
The tester will fail immediately if the gears are stripped.

The tester records all readings on a microSD card in 5 and 10 millisecond intervals for later analysis.

Here's a video showing it work:

 

This is version 0.20 hardware, still breadboard but using a single 12v supply. Software seems pretty stable for this point in the development cycle.

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I'm in the process of packaging it up as a standalone box. The tester's connector is the is the same as in the car so it plugs into the throttle body. In theory, the test can be run in the car without disassembling anything other than taking off the connector.