Someone please help me! I have a 1994 Dodge Intrepid. My check engine light stays on, but I don't understand the codes I got. 7,67,39,54,78...what do they mean? Also, my heater stays on constantly, or shuts off for amoment only to come right back on.....it's summer, I'm hot and don't need heat!

 

Some of your codes could be powertrain codes and some could be transmission codes.7 2/1 fuel system rich or 2/2 02 sensor short to ground. 39 intake air temp sensor volts low.67 1/1 02 sensor heater failure.78 2/1 02sensor fuel system lean.54 no cam signal.39 and 54 could also be transmission codes, 39 gear ratio error and 54 gear ratio error in 4th gear.