Before I got my injectors cleaned at the local tire/repair shop I used to average 16.5mpg and get around 220 miles out of a tank. Almost immediately after I had them cleaned I started getting about 180 miles out of a tank and getting around 12.5mpg. Is it possible that the cleaner messed up my o2 sensors? I've never experienced a mileage change this drastic. Could it be the opti-spark? Any ideas would help.

 

I guess it's also possible they could be out of balance. I don't think I ever got 16 on the average. I get about 12 to 14 and never had the injectors serviced.