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2014 Prius C: chugging noise and feel when accelerating w/ gas engine

Discussion in 'Prius c Care, Maintenance and Troubleshooting' started by PriusC_OCD, Nov 5, 2019.

  1. PriusC_OCD

    PriusC_OCD Junior Member

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    Hello friends, I have a 2014 Prius C model 1 that is quickly approaching 100k miles. I have put on roughly 60k in the last three years and recently I have been experiencing a slight chugging when I accelerate or am working hard to get up a big hill. It seems like the engine is struggling a bit more than usual. Especially on a longer steeper uphill, the car struggles and drops to 60 mph with the pedal down. Sometimes when starting I get a rougher idle, but this may be due to cold and unrelated. I have an OBD2 but don’t have Prius specific codes downloaded, but it is showing no errors.

    I have done all recommended mileage maintenance (with a trans fluid change at 60k which really helped some jerkiness in the exchange from battery to gas).

    Anyone had this experience? Is it a situation where I should check the plugs? Would it be an intake or valve issue?
     
  2. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    Not likely to be valve-related based on info you’ve presented.

    Plugs remain a real possibility in my mind, and fuel supply as well. Do you always get fuel from the same place?

    Also worth a quick peek at the air cleaner to make sure a squirrel didn’t fill it with the harvest.
     
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  3. PriusCamper

    PriusCamper Senior Member

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    Do you think this could be related to EGR valve and it getting clogged and gumming up head gasket to the point it might fail, or has begun to fail?
     
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  4. PriusC_OCD

    PriusC_OCD Junior Member

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    I won’t say that I use name brand gas for every fill up and would say 90% of the fill ups are whichever station is closest. I have used a few bottles of fuel system cleaner over the years.

    I also looked at air filter and looks clean, is there a space the squirrels would find room and is this different than the air cleaner?
     
  5. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    As I understand it, what you are describing is a feature of the 2ZR engine’s EGR system, not the 1NZ’s. At the very least, the EGR system in the c does not match that used in either 2nd or 3rd generation liftback.

    Wouldn’t totally rule it out either.

    Nah, the air cleaner’s the only spot I know of for rodents & associated debris.

    Spark plugs are easy in this model- to the point where it’s worth inspecting what you’ve got without committing to replacing them. Worth a peek I say.
     
    #5 Leadfoot J. McCoalroller, Nov 5, 2019
    Last edited: Nov 5, 2019
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  6. PriusC_OCD

    PriusC_OCD Junior Member

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    Is there an easy way to check this myself or to clean it without a disassembly. The videos make it look straightforward once disassembled.
     
  7. PriusCamper

    PriusCamper Senior Member

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    You could stick a camera down the spark plug holes and see if it looks clean or dirty? Hopefully other on here with more experience than I will tell you what you need to look for...
     
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  8. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    A camera in a plug hole isn’t going to tell you anything about the EGR system. It might tell you other things, but I wouldn’t bother.

    Just get the plugs out and check the tips.
     
  9. PriusCamper

    PriusCamper Senior Member

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    Makes sense, but if any plugs come out dirty than scope would be wise...
     
  10. dubit

    dubit Senior Member

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    Anyone know if there's a valve clearance inspection recommendation on the Prius C? I realize this isn't done much anymore, and on many cars it's just not needed. But there are a few Honda's that have this recommendation and it hits right at 100k (or is it 120k).

    With 100k on the ODO, I'd replace the plugs regardless of their condition.
     
  11. PriusC_OCD

    PriusC_OCD Junior Member

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    Photo is of the old (original) plugs at 98.5k. Replaced plugs with Denso IK16TT today. Was super straightforward with the C, used anti seize to a 12 lb/ft torque.

    Drove about 40 miles and the rough idle has decreased. Not sure on the mpg but averaged about 50.1 for mostly highway. I am still having some acceleration issues on hills where it feels like it’s struggling a bit. Haven’t popped any codes so thinking the throttle body may need a cleaning.

    Any other thoughts? Would EGR have any impact on idle and a bit of struggle to accelerate?
     
  12. Max Taiwan

    Max Taiwan Active Member

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    Check the valve clearance! I saw it on the manual! Can not believe it when I saw it but it seems they run on mechanical tappets.
    Coils are the next bet before the valves.
     
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  13. Max Taiwan

    Max Taiwan Active Member

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    Coils! try changing the coils. Can try buying one and replace one to trouble shoot. But at close to 100k, I would go ahead and change all 4. They should be good for another 100k!