For almost the last year my 2005 Prius has been getting low 30 mpg. I went through the usual list of tires, filters, binding breaks the usual. It was logging some misfires caused by a leaking manifold old gasket, but not a lot. No codes logged. I went ahead and replaced the injectors and after cleaning the MAF I replaced it. Hand a compression test dome,138 psi well above the 99 min Toyota specs. Took the step and replaced the traction batter. Car was now running like a dream. But still 33 mpg. Pondering the system I finely replaced the fuel/sensor that read good but did have 179,000 miles on it and it’s a bitch to get to, I had heard that these get lasy over time. That took care of it back to 45-48 mpg. I think this should be added to the lists as it doesn’t code.
