My car is running rough and acts like it is missing at times, running very rich on fuel!
I have a 1997 cavalier Z-24 racecar. We installed new plugs into the car before starting the season. We noticed that the car had what seemed like a misfire and was running rough and smoking. It was running very rich. The car has an aftermarket inline pump that is pulling from a fuel cell with clean gas. We have replaced the fuel pressure regulator with no change in the engine. I have also swapped to another set of plugs and after 30 minutes of running the car they were blackened. I have checked the system for codes and there are none on the car. I also removed the air idle control valve and cleaned it up. It acted like it helped but then the car went right back to running bad. I have not messed with the map sensor or the tps. The car has just one o2 sensor on it the other one has been replaced with a resistor. I have cleaned the throttle body and that also helped it a little. I think my next check is going to be the map sensor. Does anyone have any ideas as to what else could be used.