Low MPG, dealer says no problem ...

Wife's 2008 Prius with 46K miles. Just filled it up - 32MPG. This has been going on for a few months. We replaced the 12V battery, based on recommendations here. Still horrible mileage.

The dealer charged us $110 to check the car out, said nothing is wrong.

I am convinced the batteries are bad. I watch the "video game" and the engine is charging the batteries ALL THE TIME.

What recourse do I have? The dealer says there is nothing wrong.

As I said, replaced the 12V. Driving habits have not changed. Tires are inflated to (our) spec and fine.

Do you heir your battery fan running a lot.

It's my wife's Prius. I'm not sure. How would I describe that noise to her?

I will add that this happens even in the morning ... when the car is first started. I've see it blue when I drive to get coffee, then turn purple on the drive back. WTF? I'm looking to see if escalating to a district manager is possible. This just doesn't seem normal to me. My 2006 model was traded in on a Prius Plug-In and it had 65K miles on it and I was still getting 43-45 MPG.

what was she getting before it declined? there are so many possibilities, i would spend some time here before escalating with toyota. have you driven it for a tank to see how it does?

About 45-47. Been declining slowly (she didn't mention it to me) for months, but recently I've been tracking it, and it's been 36, 38, 38 and now 32 for the past month. The dealer sees nothing wrong when he took it for a test drive and plugged in their instruments.

has anything else changed? commute? weather? tires? etc. etc.?

Nothing that should cause a drop of what ... about 1/3? Also, as I said, we replaced the 12v battery based on things we read here. Official battery from the dealer, even.

have them test it. or if they want to charge you, there's a self test you can do. sometimes, a new 12v can be bad. i'm not saying it's not the hybrid battery, but toyota is slow to react to these things when a code doesn't pop up so you might as well keep investigating meanwhile. is it really hot where you live?

Sheesh, right, they assume that the hybrid battery is only bad if a code pops up. It's the SF Bay Area so it varies. I don't think it has anything to do with a/c, as it's been pretty temperate lately.

Iria,

Take her Prius to Luscious Garage or Art's Auto in SF. Two good, independent hybrid repair facilities.

JeffD

jdenenberg, thanks for the suggestion, but I would think if it's the hybrid batteries, it should be covered by warranty ...

You can always take it on a freeway trip and see what it does for about 40 miles or so. That would rule out terrain and driving/commute differences.

Assuming tire type & pressure, oil type & level, air-filter, and temperature extremes aren't to blame, that's an excellent next step. A steady cruise on relatively flat & windless highway can be revealing.

it might be worth a lucious analysis if you can't figure it out. if they can find it, they can fix it. if they determine it's the battery, you have ammunition to go back to toyota for warranty.

Standard tires, see dealer on time for services, checked oil, etc. etc. but it's worth a try, I suppose

If the dealer is changing the oil most likely severely overfilled. Park on flat surface and check oil dipstick carefully.
Oil must not be over fill line. I think you may fine its way over the line.
Also inflate tires to 42front-40 rear. And lastly but most importantly put the car in "ready" and then open hood and take the cap off the little reservoir next to the Inverter. Its to the left of the square shiny cover and filled with pink coolant.
While in ready look at the coolant in the reservoir with a flashlight closely. You should see really good flow/turbulence/movement of the coolant which is evidence of proper pump action. If not moving alot the pump has failed and is overheating the Inverter which kills battery mileage.

And if it was me I would change the Inverter coolant anyway. Btw, please fill out your info panel. Car and where you live. It helps us diagnose your issue.

Know any such facilities in the East Bay? We live in Castro Valley.

One other good, independent, hybrid repair facility in CA is Avi's Auto in LA.

JeffD

sorry, no.