prius just dropped mpg....what the?

ok this is worrying me and irritating me.

i bought my prius about... 3-4 months ago? it was wrecked and i fixed it (front right suspension/fender), i put... about 11000 miles on it already. i did oil change, air filter, new tires, etc... all the basics. i was getting 42mpg with a/c on in town, and about 47 on the highway. i took it on a trip to oregon, and then back down the coast and home, i averaged 37mpg (it was loaded with 5 people, and full of luggage, i did 5mph over posted speed limit the whole way so 75-80, a/c blasting the whole way). i figured the loaded down aspect was the reasoning for the low mpg, however i've been home and run 600 miles through it, and i'm averaging 32mpg last tank, and 36mpg this tank. also when i'm driving, if i turn off everything (a/c, radio, etc...) and listen down by the center of the car in the middle i swear i can hear a metallic sound....however outside the vehicle there are no audible noises...

any ideas? anything to try? this is seriously pissing me off.

 

it's a brand new optima, put in the same time as everything else mentioned above.

 

whatever discount tire sold me, pressure is still at what they put it at, seems a moot point since nothing has changed with the cars configuration since before i left on my trip (aside from my mpg)

 

i'll check the 12v for the hell of it but it's literally 2 months old so i'm not expecting to find issue there.

i seem to possibly travel on battery less than before.

 

- Have you read This Thead Yet?
Yes, i know how to drive the #@$% car.
- What fuel economy are you getting and how are you determining fuel economy? (trip computer or manual calculations)
32mpg last tank, 36 thus far this tank (trip computer)
- What fuel economy are you expecting and why?
40-42 in mixed driving, because i was getting that prior to taking the car on a 4000 mile trip
- What are the approximate outside air temps?
HOT, 110-140
- How long are your trips?
10-40 miles
- How much of it is city vs. highway? Roughly what's the average speed in overall and and of each segment? Is there a lot of stop and go driving?
70% city, 30% highway, average speed... 30mph averaged, some stop and go, i try to time the lights
- What region/state are you in? (if you haven't set your location in your profile)
Hell (phoenix, az)
- What's the terrain like of your drives? (e.g. flat, gentle hills, steep hills, etc.)
flat
- Is your oil overfilled? (i.e. above the full mark on the dipstick)
no
How old is your 12v battery? What is the voltage reading of your 12v battery after sitting over night? (Method Here)
brand new optima
Have you had your alignment checked? Any pulling or abnormal tire wear?
alignment done 3 months ago with new tires
- Are you using the factory tires and wheels? If not, please indicate tire make, model and size (e.g. Goodyear Assurance Fuel Max 185/65R15).
factory wheels, different tires, but my above mpg were on these tires.
- What are your tire pressures?
whatever discount tire set them at, and same as they were when i got the previous mpg.
- Make, model, year, engine and transmission of previous car? (e.g. 08 Honda Civic Si 2.0L 4 cylinder, manual transmission) What did you actually get on the same trips/commute? (Please give us actual numbers, not EPA ratings.)
'91 acura NSX, why's it matter. i've had 100's of vehicles.
- How are you trying to drive (e.g. trying to stay in electric only?) and how hard are you braking?
properly.
- Are you "warming up" the ICE (internal combustion engine) by letting it idle after powering on?
sometimes.
- Are you driving using D or B mode?
D obviously
- HVAC settings? Are you using the heater, AC, auto mode, etc.? If using auto, what temp is it set to?
a/c, 72 typically
- If reporting a mileage drop, did anything significant change on your car (e.g. accident, hit a curb or big pothole throwing off alignment, oil change/other maintenance/repairs, changed tires or wheels, etc.) or your commute?
No, nothing aside from taking it on a rather long trip to oregon and back.

 

ok, 12.7v on the 12v battery, and the discount tire paperwork says inflated to 33psi, my gauge says 32-33 (hard to tell the difference in 1 psi on an analog gauge) i've looked underneath and found nothing damaged, also put it on jack stands and the wheels seems to spin ok. are there any common occurrences of bearings going bad in the transmission? also the transaxle fluid is full.

 

1. because it is aired up properly and i didn't hit anything. they have 32-33psi in them front to back. and while i understand running a higher psi seems to give the prius better mpg, keep in mind this is the same psi i was at when i got previous numbers, so while that may yield an improvement, it's not the source of issue.

2. works fine, charge is within factory parameters.

 

you were fully loaded though... 5 people and cargo.. expect reduced mpg.
I specifically stated that i expected a lower mpg on the trip, my issue has nothing to do with my mpg on my trip.
my brother and I with bikes and camping gear only averaged around 35mpg or so on a long distance travel to colorado and back.

weight is a huge issue with this car vs mpg.

after any long trips with a lot of weight, check your oil.
oil is good
also.. the car kinda logs and bases itself upon your driving habbits. if you are loaded down and pulling a lot of weight, it tends to torque itself out more.. once it's just you again, it kinda has to adjust to that light load/less torque requirement.
you sure? i've not heard of such a thing (that doesn't mean anything beyond, i haven't heard of such a thing)
it's said (back in 05 or so) that if you reset the car by unplugging the 12v.. everything goes back to standard and you can kinda re train the car based off your driving conditions.

(don't ask for details.. this is years of casual chatting among people here)

plus.. a full load and anything over 65mph will get you poor mpgs... even if the speed limits are higher.. expect a reduced mpg.
you seem to be stuck on the mpg on my trip, which i was not complaining about.
since you were in a front end collision, you might want to have your inverter pump checked (or check yourself by visual turbulance) and have your normal water pump checked.. it's not in the front or too out in the open where an impact will literally hit it.. but after my front end accident, mine sounded funny and wasn't acting right, so the repair shop replaced it. (they claimed it as being on the front of the engine.. but didn't tell the insurance the front of the engine was actually to the side of the car)
for reference i have been an ASE certified mechanic since i was 22...i've also taken master classes in collision repair. so the front end was repaired properly (and i know that for a fact, not because a "mechanic" told me such). inverter pump was replaced under warranty, waterpump is fine.

now... the only flaw i saw in your own personal spec/answer sheet above is that you let the car warmup before going... you're not supposed to do this as all it really does is drain the HV battery which you'll have to make up after the car fully warms up... so.. the 1st mile or so will definitely be poor mpgs. (it all adds up)
granted i'm aware that that'll hurt my mpg mildly but over a 300+ mile average, this is not going to account for much.
i pull trailers.. am agressive with my accelerations... love speeding through mountain passes... i average around 40... pulling any weight, it drops to 37 or so. (i'm extremely mild when pulling a trailer.. i coast a lot more than when i'm solo)
i live in phoenix, everything is flat and boring. the only excitement is the ignorant drivers you have to constantly avoid.

 

oh in reply to your previous question i initially missed, i have noticed the battery cooling fan running a bit more than usual.

i do not have access to any toyota specific diagnostic equipment. the car only has 92k miles, if it weren't salvage it would be real nice to just drop it off and let the dealer fix it under warranty

i honestly think the issue is the noise i'm hearing (and the drag that would be created due to whatever the noise is). although oddly enough today there were a couple times where i was suddenly going from 38mpg, to 52-55 on the trip computer (as i usually would on the freeway), then it would kick back down (not a/c related however).

i'm really thinking about just adding up what i have into it and trying to break even on it.