I have always run mid-grade gas in it. I inherited this car and it fails emissions test. There are no fault codes, car runs well except for a loping idle and sometimes a spit and die at idle. HC and CO are way out of range. O2 reads .8v at idle.
Exhaust smells very rich.
I have replaced the ECT and TP sensors, plugs, wires and filters. Fuel pressure is 40 psi. I need voltage specs for the TP and MAF sensors. Reference voltage is 5 volts at the sensor. Fuel pressure should be 35 pounds.