Need advise please: original owner 2008 Pack 2 Prius. Not driven for 11 months between 2008 and 2012. at 135,000 miles MPG was 52.7. Pretty constant over total mileage. Haven't changed driving pattern or habits. Did change 2 things at 135,000 miles. 1. Got a 4 wheel alignment (thought it was time) 2. Put new set of Goodyear Integrity Tires on. (I know lots of bad press but I have used 3 sets of these and 1 set of Michelin, with better results from Goodyear.) Back pressure 40, front pressure 38. I always loose about 1.5 mpg for the first 10K but then back to normal. Car now has 145,000 and MPG's down to 48.5. (Now down to 48.4 after 1,500 more miles.) I have had the Inverter coolant changed. I have checked my 12Volt battery 2 ways(with meter and MFD display) and it appears o.k. 12.63 volt at jump point after 24hrs idle. 12.23Volt at jump point after 24hrs idle and car with air on. I have questioned my service rep about throtle body cleaning and he informs me that they do injector cleaning. In the past I have had bad luck with injector chemicals with O2 sensors. Is there anything else I should try before this? Can I read the MAF with a SCANGUAGEII? any help would really be appreciated Thanks very much in advance Richard
Did you replace the iridium spark plugs at 120K miles? If not I suggest that should be done now. You might also clean the mass air flow sensor. Many Prius owners would be happy with 48 mpg average, so I don't think your car has a serious issue.
Why do run 2 lbs higher on rear tires vs front? More weight in front - unless you're carrying a heavy load?
New tires will definitely lower the MPG due to higher road resistance. Alignment may change the MPG (tradeoff between stability and low resistance). It looks like the car is working fine. I won't worry about it if it's my car. Good luck!
