REF voltage should be 5.0 volts but it being a little less can happen with less than optimum connections or bad wiring. Could also point to an issue in the ECU if you get less than 5V at the ECU itself.
That is my ignorance there so my apologies. Foxes have the ten pin connectors behind the upper intake that connect the injector harness to the main ECU harness. They are also called salt and pepper shakers as one is white and the other is black. Just educated myself and the 94/95 cars do not have them.
With the Fox cars we see issues in these connectors as the pins gets spread out and cause intermittent signals or complete loss of signal. The ECT, ACT, TPS, EVP, and HEGO ground along with gauge senders run through them along with the injectors so when they loose connection it can cause some weird things to happen.
