1. Attachments are working again! Check out this thread for more details and to report any other bugs.

throttle body service prius 2016

Discussion in 'Gen 4 Prius Care, Maintenance and Troubleshooting' started by Acidburst, Aug 16, 2018.

  1. Acidburst

    Acidburst Junior Member

    Joined:
    Jun 20, 2017
    4
    3
    0
    Location:
    Usa
    Vehicle:
    2016 Prius
    Model:
    Two
    Hey guys. Sorry if this is a duplicate post but I couldn’t located a thread specific to this topic. My dealer recommended throttle body service on my 2016 Prius 2. I’ve had the car for 24 months and racked up 70k mostly freeway miles. Is there any video or instructions I could follow to do this service myself and save a couple hundred dollars? I’ve seen videos on youtube but they are for previous gen.

    Thanks in advance guys!
     
    Pyro2k and robsnyder20 like this.
  2. FuelMiser

    FuelMiser Senior Member

    Joined:
    Jun 29, 2008
    1,263
    858
    0
    Location:
    Monument, CO
    Vehicle:
    2016 Prius
    Model:
    Touring
    Can't help with the video, but I'd never pay a dealer for this. A complete waste money. I bet all they do is throw a can of gas treatment in your tank! Is your ICE running rough, or has your MPG dropped? Those would be the only times I would investigate any of this action.
     
    kithmo, goldfinger, ETP and 1 other person like this.
  3. Starship16

    Starship16 Senior Member

    Joined:
    Jun 8, 2018
    1,348
    1,452
    0
    Location:
    Beach Christmas
    Vehicle:
    2016 Prius
    Model:
    ----USA----
    Service department trying to make a few extra dollars?
     
    #3 Starship16, Aug 16, 2018
    Last edited: Aug 16, 2018
    kithmo, goldfinger, Tande and 2 others like this.
  4. BuickGN

    BuickGN Junior Member

    Joined:
    Aug 16, 2018
    25
    48
    0
    Location:
    Los Osos
    Vehicle:
    2015 Prius
    Model:
    Two
    Absolutely do not do it. Your car has an air filter, right? lol. The front side is always clean. Over time, the back side of the throttle body can get a small buildup of EGR and PCV "crap" on it. It hurts nothing. Below 150,000 miles it will only be slightly discolored, maybe even black with a film on it. Once the buildup starts, if bad enough, it will hurt idle. In rare cases it can cause a low idle since the throttle valve (butterfly valve) is barely cracked open at idle and a little gummy stuff can block the already small amount of air that's getting past the valve to run the engine. If the car is idling ok which I'm sure it is, do not do this.. Don't consider it for another 100k if ever. It's a way of making money... 5 minutes of labor (remove the intake pipe, open the throttle valve, take a rag with solvent and wipe the flap and the bore where it closes). Minutes of labor and practically zero in materials.

    This can't lower mileage. It could be plugged so bad that the bore is 1/2 it's original size, it will not hurt mileage. Just like a high flow filter can't help mileage. The throttle valve controls airflow/power. It's mostly closed at idle and fully open at full throttle. If a high flow filter helped mileage or a dirty throttle valve hurt mileage, the car would get better mpg at full throttle and lower mpg at idle.

    If you're curious, remove the intake pipe after the filter that bolts to the throttle body. Look inside of it for yourself. It will be a clean aluminum bore with a brass colored "flap" that opens and closes with the gas pedal. Open the valve to look at the back side. I'm not too familiar with the Prius so maybe others can tell you how to open the throttle valve. Just don't pry it open. Usually you can have someone floor the throttle with the engine off to open the valve but that would likely fire up the engine so it would have to be disabled first. It might be easier to just remove the throttle body to see the back side of the butterfly valve. But again, unless you're having low idle problems, the TB is fine.
     
    Pyro2k, RCO and ETP like this.
  5. alanclarkeau

    alanclarkeau Senior Member

    Joined:
    Feb 24, 2016
    7,041
    7,580
    0
    Location:
    near Brisbane, Australia
    Vehicle:
    2016 Prius
    Model:
    N/A
    Dealer looking to make some more money. Freeway miles are generally kinder to an engine than round town. Don't forget that a fair percentage of that 70k, the ICE hasn't been running anyway - you'd have at least 25% EV, if not more.

    I've only done it once - on a VOLVO with about 200k km on it. My Dad's CAMRY with 300+k km on it never had the throttle body cleaned, it was starting to run a bit rough. We put a bottle of this in it, and it ran better afterwards.

    If you really want to do something, you could put some of this in the tank - some mechanics suggest it, but mostly on higher kilometre engines:

    upload_2018-8-17_10-44-39.png
     
    RCO, Starship16 and ETP like this.
  6. ETP

    ETP 2021 Prime(Limit),Highlander HYB Plat,B52-D,G,F,H

    Joined:
    Apr 12, 2009
    2,799
    1,170
    0
    Location:
    Auburdale FL
    Vehicle:
    2021 Prius Prime
    Model:
    Limited
    Exactly. Took my Prius in for the 30K check and they said it needed a brake flush. LOL Sure! I have never flushed any brakes in a Prius / ever and do not plan too. Sort of like feeding hungry lions inside the cage with blood all over you.

    If I notice my MPG goes down I will throw a can in the tank and check my filters and tire pressures.

    Now the tranny fluid is open for debate. It is hard to get a decent price for the dealer to do this and I am not able to do it. If I trade every 50K then I may skip it from now on.
     
    Starship16 likes this.
  7. alanclarkeau

    alanclarkeau Senior Member

    Joined:
    Feb 24, 2016
    7,041
    7,580
    0
    Location:
    near Brisbane, Australia
    Vehicle:
    2016 Prius
    Model:
    N/A
    That's really unusual - brake fluid on just about every car is changed every 2 years - just about every brand specifies that. Maybe it's a special type of fluid in PRIUS?

    I just checked the PRIUS Service (USA) Manual and it's not listed as ever needing changing. At my last service (2yr/40,000km) I know they changed the brake fluid. I'll check my Service Manual next time I'm at the car to see what's specified there.

    Same with Auto Transmission - the manual goes to 120,000 miles and it only mentions changing it if towing or H/D driving.
     
    Starship16 and ETP like this.
  8. ETP

    ETP 2021 Prime(Limit),Highlander HYB Plat,B52-D,G,F,H

    Joined:
    Apr 12, 2009
    2,799
    1,170
    0
    Location:
    Auburdale FL
    Vehicle:
    2021 Prius Prime
    Model:
    Limited
    Brake flush in a Prius is not easy or simple like most cars.
    I will check the US manual.
     
    Starship16 likes this.
  9. ETP

    ETP 2021 Prime(Limit),Highlander HYB Plat,B52-D,G,F,H

    Joined:
    Apr 12, 2009
    2,799
    1,170
    0
    Location:
    Auburdale FL
    Vehicle:
    2021 Prius Prime
    Model:
    Limited
    OK, US manual never mentions a brake flush and allows an optional tranny fluid change at 120K.

    Just like you said.
     
    Starship16 and alanclarkeau like this.
  10. Acidburst

    Acidburst Junior Member

    Joined:
    Jun 20, 2017
    4
    3
    0
    Location:
    Usa
    Vehicle:
    2016 Prius
    Model:
    Two
    Thanks a lot for all your input guys. The transmission flush was another thing they recommended too.
     
    ETP likes this.
  11. ETP

    ETP 2021 Prime(Limit),Highlander HYB Plat,B52-D,G,F,H

    Joined:
    Apr 12, 2009
    2,799
    1,170
    0
    Location:
    Auburdale FL
    Vehicle:
    2021 Prius Prime
    Model:
    Limited
    Remember it is just a drain and fill (3.5 ish quarts) and not a flush. They try to charge you for a flush of an automatic transmission most of the time. If you get an honest dealer and they actually do it it should cost between $69 and $89
     
    Starship16 likes this.
  12. Starship16

    Starship16 Senior Member

    Joined:
    Jun 8, 2018
    1,348
    1,452
    0
    Location:
    Beach Christmas
    Vehicle:
    2016 Prius
    Model:
    ----USA----
    Acidburst... your username reminds me of my stomach. :LOL: Too many Tacos.

    I just buy good gas, Chevron Techron, and once a year dump in a separate bottle of Techron fuel cleaner into the tank. Don't know if any of that helps. I might try the Toyota brand fuel treatment next time, as Alan suggested.

    And I might have one transaxle fluid drain/refill done sometime during the life of the car. I bought a Prius because they are supposedly low maintanence. :)
     
    #12 Starship16, Aug 17, 2018
    Last edited: Aug 17, 2018
  13. alanclarkeau

    alanclarkeau Senior Member

    Joined:
    Feb 24, 2016
    7,041
    7,580
    0
    Location:
    near Brisbane, Australia
    Vehicle:
    2016 Prius
    Model:
    N/A
    I think I used WYNNS fuel cleaner last time - it was the one the VOLVO mechanic suggested - said it worked as well as any in his estimation.
     
  14. robsnyder20

    robsnyder20 Active Member

    Joined:
    Aug 13, 2012
    372
    300
    0
    Location:
    SW Florida USA
    Vehicle:
    2016 Prius
    Model:
    Three
    Ok I had two different dealers recommend the throttle body service and the last one said the mass air flow sensor needed cleaned as well so being that I am familiar with servicing my previous Toyota prior to my brand new prius I gave it a go. It was a 15 minute job (well 45 minutes if you count dropping a dog-gone stubby phillips screwdriver in the bottom of the engine and have to go fishing for it). I was rather unhappy once I pulled off the connecting hoses and found it clean as a whistle. I am posting pics of it once I pulled it apart and this was taken BEFORE I cleaned or sprayed anything onto or into the intake.

    I, Like the rest of you looked for some videos of how to remove the hoses and couldn't find anyone whom posted any but basically you need a 10mm socket and a small rachet or a stubby phillips head screwdriver and can unscrew the hoses that connect the box to the air intake and you also have some other hose clamp that I was able to squeeze using my fingertips and undo and everything easily comes apart. I would say looking at mine, this would be more like 100k job for most people unless you are in a dusty or dirty environment or throwing some kind of code on the CPU.

    For the mass air flow sensor that connects to the box with the air filter, you will need a small phillips head and a small flat head (for the electrical connector clip) and its two screws and it comes right out on top. Very easy to take apart and put together.

    They also recommended a fuel system flush but I never even had that done on my other toyota car with 333k miles on it when I got rid of it. I usually throw a bottle of techron every 10k and put some premium fuel when running that thru. No idea if I'm just wasting my money here or not but figure it can't hurt. 0823181906_HDR.jpg 0823181906a_HDR.jpg IMG_20180823_191353.jpg
     
    RCO and Starship16 like this.
  15. alanclarkeau

    alanclarkeau Senior Member

    Joined:
    Feb 24, 2016
    7,041
    7,580
    0
    Location:
    near Brisbane, Australia
    Vehicle:
    2016 Prius
    Model:
    N/A
    Thanks. How many kilometres has it done?

    I think that's our suspicion, that it would be like new - but now we know they're just trying to add to the dealership's coffers. One wonders if they'd have a look, and then connect it all up without actually doing anything (apart from fishing out their screwdriver)?

    [That's not bad for lost time - I once lost a sparkplug down in the tinware of a 2 litre VW Flat Aircooled engine. Eventually got it out, but with a magnet on a non-magnetic rod. It was an afternoon long job - might have been easier to disassemble it.]
     
  16. robsnyder20

    robsnyder20 Active Member

    Joined:
    Aug 13, 2012
    372
    300
    0
    Location:
    SW Florida USA
    Vehicle:
    2016 Prius
    Model:
    Three
    Sorry 40,000 miles or 64,000 km
     
    alanclarkeau likes this.
  17. Starship16

    Starship16 Senior Member

    Joined:
    Jun 8, 2018
    1,348
    1,452
    0
    Location:
    Beach Christmas
    Vehicle:
    2016 Prius
    Model:
    ----USA----
    Nice pictures. Very clean!

    I was reading the Techron website, and they recommend pouring it in the gas tank every 3.000 miles. Seems like a bit much, but maybe not. That's probably 4 times per year for the average 12,000-15,000 mile driver. (Or maybe it's just marketing hype)
     
    #17 Starship16, Aug 27, 2018
    Last edited: Aug 27, 2018
  18. BuickGN

    BuickGN Junior Member

    Joined:
    Aug 16, 2018
    25
    48
    0
    Location:
    Los Osos
    Vehicle:
    2015 Prius
    Model:
    Two
    I’m glad that those throttle body pics show what I was saying. Only filtered air gets to the throttle body. The front will look nearly new for well past 100k. The backside sometimes gets a very slight buildup of carbon from the EGR and PCV systems and reverbration.

    This layer of stuff does nothing to hurt performance. The only way a dirty throttle body can cause problems is a low idle speed by sealing up and not letting air past the throttle blade. If it’s not idling low which it’s not with under 200k on it, no need to clean it.

    One other thing, a dirty air filter can’t hurt mpg and a higher flowing air filter can’t help mpg. The engine is throttled by the throttle body. Blocking off air reduces power and increases mpg. Fully open gives max power and the worst mpg.

    How does a plugged filter that only does what a partially closed throttle body does hurt mileage? How does a high flow filter that reduces intake tract restriction the same as opening the throttle body for more power help mpg?

    In real life, the filter is spec’d so that it’s invisible to the engine even at full throttle and with some contaminate loading. It offers no restriction. This is even more true from idle to part throttle (closed to partially open TV) where airflow is lower than a fully open throttle valve at full throttle.

    Air filters can’t affect mpg since the throttle body determines restriction/airflow, less airflow equals better mpg, the AFR is not altered by this intake restriction, with the exception being a carbureted engine. If you cause a restriction upstream of the carb it will at like the choke and richen the mixture but luckily we don’t have to worry about this.

    As for the MAF sensor, cleaning is typically not necessary unless you get it oily from a K&N filter which dies nothing for power anyway. I admittedly haven’t looked at the type that’s used on the Prius but if it’s the typical hotwire style, they usually self clean by sending a voltage to heat up the sensing wire to yellow hot to burn off contaminates on shutdown. I wouldn’t mind knowing what style these cars use. Maybe I’ll look tomorrow.

    Don’t forget that the O2 checks AFR post combustion so correction is applied via O2 feedback as needed as sensors such as the MAF drift over time. This correction used to be displayed as Block Learn and Integrator values to show how much correction and whether fuel has been removed or added to the original calculations. This even compensates for very small vacuum leaks and tolerance stack up of various components. It’s still very important to have a clean MAF for best mpg but it’s very unlikely to ever need a cleaning and the post combustion feedback portion won’t let things get too out of whack should a sensor really drift or fail.
     
    RCO, krmcg and robsnyder20 like this.
  19. BuickGN

    BuickGN Junior Member

    Joined:
    Aug 16, 2018
    25
    48
    0
    Location:
    Los Osos
    Vehicle:
    2015 Prius
    Model:
    Two
    I’m a premium fuel user, mostly for the additional detergents. I use Shell and Chevron and alternate between them. One works well on anything fuel can touch, namely the fuel system and back sides of the intake valves. The other works better in keeping the crank case and PCV system (intake manifold included) clean, whatever combustion blowby gasses come into contact with. No in tank cleaner will do anything for a throttle body nor should it.

    I have no issues in using 87 octane in this car and when I fill up at the only pump at work, it’s 87. I just prefer the additional concentration of detergents in 91 (in the right brands) and shoot for at least half of the fuel used to be premium fuel.
     
    krmcg likes this.
  20. robsnyder20

    robsnyder20 Active Member

    Joined:
    Aug 13, 2012
    372
    300
    0
    Location:
    SW Florida USA
    Vehicle:
    2016 Prius
    Model:
    Three
    Didn't get a pic but the closest I could find (and nearly looks Identical to this performance one from JCwhitney) looks like this one with the piece of metal on the side and the other side it has some diodes which appear that they may need cleaned every so often. I cleaned Mine with some CRC mass air flow cleaner spray I had working on my other toyota. Admittedly I doubt it needed it but I put probably 500 miles and thankfully no issues with doing the work myself.

    mass1.PNG mass2.PNG
     
    #20 robsnyder20, Aug 30, 2018
    Last edited: Aug 30, 2018