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Toyota Prius Repairs

My Toyota mechanic tells me my 2008 Prius with 83,000 miles needs the following service: Mass Air Flow Sensor and Throttle Body Service. He says this will give me better performance (I already get 48.6 mph - how much better could it get??). How can I tell if I need to do this work?

NO, if car is running ok - this is just fluff stuff. Makes money for mechanic with no benefit to owner.

If anything was wrong with these parts, the “check engine light” would come on or you would notice an engine performance problem…“Servicing” these items usually involves no more than cleaning them with a spray-can of cleaning fluid…

It sounds like your mechanic is fishing for a “boat payment.”

Have you always been getting around 48 mpg? If so, I wouldn’t worry about it.

The few Priuses (“Priui”) I service routinely show low 50’s mpg, so it could get a little better, but so much of that depends on the driving habits and the age of the car. Symptoms of a dirty throttle body include low or poor idle quality. Mass Air Flow sensors can begin to fail without being bad enough to cause a check engine light. A good technician can find a dirty throttle body and a failing mass air flow sensor on a test drive without even opening the hood. On the other hand, if you’re not experiencing any problems you may not want to start looking for them.

Sounds like the same mechanic who told me it would cost me $750 to replace the mass flow sensor even though I had already had three of them replaced under warranty for my yellow beetle.
I told him to put the car back together so I could talk to manufacturer. The light went off and didn’t return for seven months…at which time VW replaced the sensor for no charge.

They fired the mechanic since he was billing the manufacturer and charging the customers.

48 mpg sounds normal and as someone mentioned your driving habits might raise it but I can’t blame it on a faulty sensor.

I would tell the owner of the dealership or shop. If that is the owner go somewhere else.

I have a brand new Prius and get 48-50 mpg.

" A good technician can find a dirty throttle body and a failing mass air flow sensor on a test drive without even opening the hood."

Perhaps not on a Prius with it’s indirect drive system…

“” A good technician can find a dirty throttle body and a failing mass air flow sensor on a test drive without even opening the hood."

Perhaps not on a Prius with it’s indirect drive system… "

Sure, piece of cake. The internal combustion engine is plain-jane Toyota fuel control stuff. A routine road test while graphing sensor data from TPS, MAF, long and short term fuel trims and O2 sensor data will give you all the info you need.