It seems that I remember reading there are two coolant temperature sensors on the 2nd generation one for the gauge and one that reports to the ECU for fuel mixture. Is this correct or did I somehow dream this up? The gauge is reading correct. I've looked on Rock Auto and can only find one ECT sensor. If there are two someone please tell me how to find the other one on Rock Auto. Something is definitely screwing up my gas mileage on the '94. I've replaced plugs/wires both of which it needed, PDFE sensor which I had a code for, cleaned the MAF sensor and located and repaired a vacuum leak yet the mileage is still low. This leads me to believe it's a problem with the ECT sensor or the O2 sensor. I have a brand new O2 sensor here at the house but can't seem to get anything on it where I can turn it to remove the old O2 sensor for the a/c lines.