Well the code list says it's either a low IAT or a throttle position sensor error.

Seeing as this is the desert, I would suspect that it isn't the low IAT.

Is there a way to test a TPS? Would resetting the TPS be a good step?

 

I don't know what the initial voltage should be for a 92', for my 88' it's 0.54 volts, as you slowly open the throttle the voltage should increase smoothly, no sudden jumps (dead spots.)
If the voltage is per your car's specification, I wouldn't touch it.

 

Your '92 should have a fixed TPS - Non-adjustable. The ECM will read the voltage from the TPS at ignition power-up and presume that to be the closed throttle position. Any change from that voltage is considered to be an opened throttle to some degree.

There is one caveat. The voltage from the TPS must be below 0.9V at start-up, or the ECM may not be able to capture the value as a closed throttle indication. If the closed throttle voltage is too high, the throttle stop screw may have been tampered with, the throttle shaft/lever may be damaged, the TPS may be defective, or the 5V reference voltage to the TPS may be too high (bad reuglator in ECM or wiring problem).

Also, any lowering of voltage below the "base" point learned at start up will set an error code. You can test for that as "63" described, by operating the throttle while measuring sensor voltage.

 

It was a simple fix. The IAT plug came loose. Plugged it back in and seems to be ok.