Where do I start? The car will have an erratic almost rough idle once it has warmed up. Then while driving it the car will stumble kind of like a misfire and you can feel the hesitation in the forward movement. I check the codes and it came up with 12 and 77. While researching those code I found them to be the battery has been disconnected and it has been. The other code is Speed control power relay circuit. It's failing to open or its shorting. I have looked for this sensor on diagrams and can't find it. If its location is in the owners manual I will find it once I can get the manual. Some other posting have suggested something to do with problems in the cruise control system. I also have a problem with the HVAC system just blowing lukewarm air, not heating the vehicle very well. I don't think these issues are related but I'm not sure because I have read about some defect in a wiring harness. If you have experienced any of these problems and or you can help me in fixing them your help will be greatly appreciated. I have to start somewhere so any and all suggestions may help. Thank you very much.