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101k now / Never done any maintenence, now i'm getting poor mpg. What do I do?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by 240sxer, Apr 5, 2010.

  1. 240sxer

    240sxer New Member

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    I just hit 101k miles on my 2006 Package 6 Prius. The only maintinence i've ever done is change the oil, air filter, cabin filter, and tires. I've never done ANYTHING else to it. original brakes, original alignment, original suspension, stock everything.

    I used to commonly get around 44mpg, lately, in the last 4k miles or so I've noticed my MPG get worse and worse. It's now only at around 37mpg usually. First the first 90k miles I've only had maybe 2-3 tanks below 40mpg, now it's all of them.

    What should I replace or change? I'm ready to do it all now. I know I should have done stuff earlier, but that's water under the bridge now. Any clue why my fuel economy is suffering? Maybe spark plugs?

    I can do most/all of the work myself, but if I'd be better off going to Toyota for all the service that's fine too I suppose.
     
  2. bisco

    bisco cookie crumbler

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    you're really just in time for the first major service, check your owners manual.
     
  3. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    At a minimum:
    Replace engine oil and oil filter
    Rotate tires
    Replace engine and inverter coolant
    Visually inspect brake linings/drums and brake pads/discs

    Replacing the coolants may be pricey, but they are old now. After this, every 50,000 miles.

    I would be very suspicious of your 12v battery, it may well be 4 years old or more, and in my experience 4 years is old for any 12v car battery. Some symptoms of a dying battery include constant charging, (reduced MPG) odd 'Codes' from the computers, and forgetting settings like door locks and beeping.

    eLearnAid has a battery conversion that my interest you.

    12 Volt (12v) Toyota Prius Auxilary Battery for 2004, 2005, 2006, 2007, 2008, 2009 and 2010 with installation kit
     
  4. donee

    donee New Member

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    Hi All,

    Old Spark Plugs are a common source of poor mileage in cars. Less so now with modern electronic engine controls, but still, 100K miles on plugs is going to be it.

    Also, have the throttle body mechanism and mass flow sensor cleaned.

    And a bottle of fuel injector cleaner is probably a good idea too.

    If all the stuff mentioned does not do it, then maybe a look into the exhaust system components.
     
  5. 2009Prius

    2009Prius A Wimpy DIYer

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    I would first check the 12V battery as well.

    Some posters had bad experience with fuel injector cleaners. I would not risk it.
     
  6. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Here are the items I would check:

    1. Tire pressure
    2. Wheel alignment
    3. Parking brake drag, raise up the rear of the car and see if you can easily spin the rear tires when the parking brake is off
    4. 12V battery becoming marginal
    5. Clean throttle body, throttle plate, and MAF sensor
    6. Replace iridium spark plugs now, rather than waiting for 120K miles

    Although the following items will not negatively impact fuel economy, they are due now:

    7. Engine and inverter/transaxle coolant replacement
    8. Transaxle fluid replacement
    9. PCV valve replacement
    10. Serpentine belt replacement
     
  7. richard schumacher

    richard schumacher shortbus driver

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  8. 240sxer

    240sxer New Member

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    Thanks for all the assistance. Yes, I'll definitely get a new aux battery. It died one a few years back so I'm sure it's life is pretty much up even if it's still working.


    So i'll be doing Battery, Engine and inverter/transaxle coolant replacement, Transaxle fluid replacement, Serpentine belt replacement and spark plugs.

    Where is the best place to get all these products?
     
  9. edthefox5

    edthefox5 Senior Member

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    I bought an S13 in 92 brand new. 4 speed. Loved that car. Had it for 14 years. Sold it to a kid who was into drifting. Never should have sold it but it needed to much chassis and interior work. Bushings....There's a huge 240 2.0 group in town here. You can't beat a 12 second 240SX right?
    Been to Freshalloy.com?
    I lived there for years. So many tuners there use Redline Trans lube.
    I'm running Redline D6 in my 07' Prius trans . Runs great. Almost at 22,000 miles on that fluid. Your way overdue on the trans change.
    Try it.
     
  10. 240sxer

    240sxer New Member

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    Cool can you give me a link or something for the Redline fluid?

    My 95 S14 actually had a single turbo 2JZ-GTE in it (supra turbo), it made around 470whp on pump gas. With a TH400 transmission it ran in the 10s on pump gas.

    I got rid of it because I've realized that it had no point but to just go fast. I wanted to do something where I can race professionally so I've got a Spec Miata racecar now.
     
  11. JimboPalmer

    JimboPalmer Tsar of all the Rushers

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    eLearnAid is a good source for the battery, if it is dying.
    12 Volt (12v) Toyota Prius Auxilary Battery for 2004, 2005, 2006, 2007, 2008, 2009 and 2010 with installation kit
    I would go to a Toyota dealer to get the fluids. I bet any auto parts store will have belts and plugs, if you want to do it yourself.

    Quote from http://priuschat.com/forums/gen-ii-...70-what-services-you-need-what-you-don-t.html

    "3. transaxle fluid
    there is no way to "flush" the trans on a prius. if someone tries to sell you this, run. they can drain and fill, however. the fluid is expensive and is supposed to go 100k, but you can never go wrong changing it early. in most cases it isn't necessary. this is the same fluid that goes into a tundra for 100k under towing conditions. the only complication you might see is again due to tech error- using the wrong fluid or not filling all the way.

    4. engine and inverter fluid
    drain/fill is OK, but NO flushes. it's not even possible on the inverter and the engine is difficult but not impossible, however NOT recommended as it can cause serious damage to the electric water pump and switching valves. you do not need the drain/fill until your car hits 100k. if the coolant is still nice and pink, don't do it then either. again, the coolant is said to go 100k. while you're not going to do any wrong by changing it early, again it is expensive like the trans fluid. possible complications include more tech error- bleeding these systems is a PITA and getting all the air out is hard. an incomplete fill, use of the wrong coolant, can damage your car."
     
  12. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Regarding the 12V battery, Toyota SLLC, and Toyota ATF WS, you may want to call your local Toyota dealer parts dept to find out their pricing. MSRP is $139 on the battery. SLLC is ~$20 per US gallon, you'll need 3 gallons. ATF WS is ~$9 per US quart, you'll need 4 quarts.

    Regarding the serpentine belt and iridium spark plugs, there are a number of Toyota dealers that sell parts over the web at 25% discount from MSRP. For example, Champion Toyota Parts - Toyota World, Genuine Toyota Parts, TRD Supercharger, Toyota Venza Parts, Toyota Parts, Toyota Accessories, Discounts on Toyota Parts

    The belt is ~$20 and the spark plugs are ~$10 each.
     
  13. richard schumacher

    richard schumacher shortbus driver

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    If you don't use Toyota Prius ATF you may damage the electric motor/generator windings which are exposed to the fluid. Others may be safe, but why risk a $2000 trans-axle replacement to save $10?
     
  14. 240sxer

    240sxer New Member

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    Ok, I purchased the battery, I'm looking for a good site to purchase the other items I'll need.
     
  15. edthefox5

    edthefox5 Senior Member

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    470whp and in the 10's is crazy fast. Thats with the Supra 3.0? Thats awesome. I really like the looks of the S14 too. Thats the hot set up on some Lexus's too. I've seen a bunch of Lexus SC300's on You Tube with the same set up. Unreal horsepower.

    Here's the link: Red Line Synthetic Oil - Automatic Transmission Fluids - D6 ATF

    Need a gallon. 3.8 qrts to be exact.

    My 07 runs great on it.
     
  16. 240sxer

    240sxer New Member

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    I sold the 240sx because it was too fast and got boring. There is NOBODY on the street that can compete so there are never any good races. I got a Spec Miata racecar now and I road race. Much more competitive and fun.

    So would it be better to run Redline ATF or just the factory Toyota ATF?
     
  17. usbseawolf2000

    usbseawolf2000 HSD PhD

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    I would go with Toyota ATF unless Redline can prove that their ATF is safe with the electric motor windings in Prius hybrid transaxle.
     
  18. jayman

    jayman Senior Member

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    I don't think we're going to easily resolve the issue of electrical properties of WS vs another ATF

    Consider that WS is used across the board in Toyota automatic transmissions. That means it must have an additive package that allows the torque converter to operate without shudder, the clutches to engage smoothly without slipping or harsh engagement, etc

    Typically, a pure electrical oil, like those found in transformers, would NOT be appropriate in an automatic transmission. Or, if you refilled an industrial transformer with WS, there would probably be fireworks once you threw the switch

    There are a few folks on this forum who have chosen to not run WS in their Prius. Until we see evidence of failures, it's probably safe to say its ok to run a different oil. All depends on how long we are willing to wait for these failures to pop up: a year, 5 years, 15 etc
     
  19. edthefox5

    edthefox5 Senior Member

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    Many posters here are running many different brand trans flluids. Even Walmart offers a compatible WS fluid. Yikes....

    I am a Redline gear oil fan. They make an excellent GL-4 lubricant. Full synthetic. Been using it for years and years.There MT90 fixed my second gear snick on my S13 too. Its the shit.
    In my 07 prius I'm going on almost 2 1/2 years on my D6 fill. D6 is full synthetic. Trans runs great. Smooth smooth. Our CVT's are not that persnickety. There a chain drive planetary gearbox. Just a big well engineered gear box. Keep high quality clean gear lube in it and it will outlast you.

    BTW, Toyota's recommended CVT fill is 100K. Poster after poster report black fluid at 100K. With no problems.

    Try a D6 fill and tell me you don't hear and feel a difference. I wouldn't lead an S13 brother wrong. I intend to change the trans fluid every 30,000 miles. Its cheap and easy. A gallon of Redline is what $40 + ship?

    Soon as I buy a car its Mobil One in the motor and Redline in the trans and rear. Most of my new cars have never seen a dealer lift throughout there life. I intend to keep it that way with my Prius.
    Only time my 27,000 mile Prius has seen a dealer is when it drives me there to buy an oil filter. Then I get the hell out of there.....
     
  20. jayman

    jayman Senior Member

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    Funny you mentioned that. When I got my '07 FJ, brand new, early reports of rear end problems had already come out. Back then, Toyota had this really weird gear oil recommendation for the rear axle

    They wanted you to use a straight SAE 90 GL-5 in the rear end, but only if the temps were above 0 F. No doubt, trying to use a straight SAE 90 in winter, the oil will turn solid and you'll destroy the pinion bearing, pinion gear, and cause rapid axle destruction

    Makes me wonder about all those early FJ's shipped from Japan with SAE 90 in the rear axles - perhaps that alone explains the rear axle problems, that and poor quality R&P sets

    So, with about 1,200 km on my FJ, I drained all the gear oil, The rear axle oil was already BLACK, that was highly unusual and very unexpected. I refilled with a commercial heavy duty gear oil I trust

    Mobil Delvac Synthetic Gear Oil 75W-90, 80W-140

    What surprised me was the vehicle became much quieter. What I assumed to be exhaust resonance from the rear, was actually a growl from the rear axle. Even gained 1 mpg, not a huge difference but a difference

    Toyota officially poo-poo'd the idea of running synthetic in the axles. Some FJ owners even received snotty letters from their dealership AND from Toyota warning them that their powertrain warranty was void because they admitted to running a synthetic gear oil. That the synthetic gear oil wasn't "thick" enough

    Then, in late 2007, Toyota issued a TSB for the FJ and 4Runner. Effective the date of the TSB, November 8 2007 (TSB DL003-07), all FJ's and 4Runners were factory filled with a special Toyota synthetic 75W-85

    So, the new factory fill and dealership synthetic gear oil is quite a bit thinner than the old recommended straight 90 gear oil, and a bit thinner than normal 75W-90 synthetic gear oil. And that appears to have resolved most of the axle failure problems

    Which is something us FJ owners sort of realized when we heard noises from our rear ends, and discovered thick, black, sludgy gear oil in there from the factory