Why can't I get a tuneup?

The plugs in your car are rated to last 100k miles, have you checked other mileage robbers? Tire pressures, 12 volt battery, are you carrying more stuff in the car this year?

 

IMO, tune-ups are for older cars with points, carbs, and the like that constantly require adjustment/tuning. When you say tune-up on a car like the Prius I think of a service interval, change filter, plugs, oil, and so forth. So maybe the stealerships techs heard tune up and said 100k because that is when your plugs are due.
I would call another stealership, or a Yota specific mechanic to preform the service you desire.

 

What's a tuneup?

 

I'd guess the biggest difference is that, for cars of much older vintage, "a tuneup" was an actual, expected thing to have to do. Those cars had a bunch of minor, relatively inexpensive, parts known to wear out or deteriorate sort of rapidly with use (points, condenser, distributor cap, rotor, plug wires, spark plugs) and it made sense to have a regularly scheduled job where you would just change all those en masse because it was easy and cheap and they probably needed it, and the engine was probably running poorly by that time and would run better when you were done.

Fast forward to your Prius, and out of that whole list, spark plugs are the only things it still even has. And those are iridium-tipped and I've only changed mine twice in the time I've had my car, and one of them was in less-than-perfect condition, the first time.

Because of the almost complete elimination of those minor, nuisance, wearing out components in the engine, the whole experience of running-gets-rough, buy-magic-cheap-bag-o-parts, fling-them-on, engine-all-better-again just really isn't a thing any more. It's not that it's never possible to develop an engine issue, it's just that if one does develop, it's much more likely to be the result of some identifiable problem, where it makes more sense to just find what that problem is and fix it.

-Chap

 

both of those people should have recommended the toyota 90,000 mile service. it is the modern equivalent of a 'tune up', the most important part being you air filter. if that, ture pressure and 12v battery don't help your mpg's, you'll need to search here for things like throttle body cleaning, pcv valve, injectors and etc. all the best!

 

When I ask for a transaxle fluid change, my mechanic comes to me in the waiting room, and tells me it is not due yet. When I explain I am using a more aggressive schedule than he is, he does it even though it is not due. This is ideal if you think about it, not overselling, but not refusing the customer's desire either.

The only other items that even seem 'tune up'y on a Prius are Spark Plugs, and the PCV Valve. Someone should sit you down and tell you they are not yet scheduled, then take your money.
Every
Oil 10,000 miles/12 months
Oil filter 10,000 miles/12 months
Air filter 30,000 miles/36 months
Cabin Air filter 30,000 miles/36 months
Spark Plugs 120,000 miles/144 months
PCV Valve Seems to be warrantied for 80,000 miles/ 8 years, but to specified replacement mentioned, I would replace it at the same time as the spark plugs.
ATF WS in Transaxle no mention of a replacement interval in the manual, I use 30,000 miles, 90,000 miles then every 90,000 miles

I would guess that eventually Brake fluid would need replacing at the Dealer (it is non trivial) but that would be based more on humidity than mileage.

Same story, eventually the coolant (both loops) needs replaced, but I would not do so based on mileage.

 

You need to download the owner's manual (or dig it out of the glove box) and read the schedule of maintenance.

What you're dealing with is a very rare.....**VERY RARE*** example of a dealership that is not trying to use your lack of familiarity with the G2 to make some extra boat payments.

There is no such thing as a tune-up any more.
The schedule of maintenance will detail what should have been done to your car by now, and what is not needed at this time, and the dealer might have a history for this car if you or the previous owner did maintenance with a dealership so you don't double tap things like transaxle fluid replacement,

One of the good things about Priuses?
They require very little maintenance---just like most modern (post 2000) small, 4 cylinder, 5-pax, FWD cars.
Get the history to see what's been done, find out what's needed right now and get back to us.

A sudden 5MPG drop isn't a maintenance issue....it's a repair issue.
There's a guide out there somewhere for that.
I'd be looking at things like tire pressures, oil level, 12v battery health, brakes, etc.