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P2111 Code after probably bad fuel top up

Discussion in 'Prius c Technical Discussion' started by Terror404, Jan 23, 2022.

  1. Terror404

    Terror404 Junior Member

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    Hello,

    2015 Prius C with 110 miles on odo

    Some days ago I had topped up my fuel tank with fuel at suspicious fuel station (as it turned out afterwards). I had almost half tank of fuel but as I was on my road trip decided to top up on my half way. Car stalled at first junction and p2111 code came up. I called for the roadside assistance and tried to solve the problem next day.

    As per code, throttle valve body seemed to be the problem and "Engine failed to start" was mentioned in Techstream . I cleaned it but without success. After cleaning the code, car starts normally, but as the engine gets up to the operating temperature code comes up again and car stalls.
    I suspected that fuel had some water in it (it was freezing as well that day ) and did not wait long and drained all fuel from the tank (disconnected the fuel line and started the pump manually with 12v). Then I poured in some new gas and car started without any issues. I drove for several days like that for about 500 mls. After that I parked car for 2 days and the problem reappeared :(( It was also quite freezing that day and I suspected that water condensated in the tank. I did not repeat the fuel flushing but removed the fuel pump to investigate if there was any debris/ water inside it. Pump and filter turned out to be clean, also some droplets of water were found inside the pump sump. I cleaned it and reassambled everything. Started the car and guess what? problem is still there. I do understand that I had to replace throttle body in the first place, but damn it is too expensive and if it had a real problem, car should not have moved for 500 mls without an issue.

    Now I am kind of perplexed and do not know what to do next, except of changing the throttle body of course, which I will do as soon as I get back to the city. The place I am now I can only do basic maintenance by myself.

    So any suggestions?

    I was planning : 1. Cleaning up EGR and intake manifold 2. adding some amount of ethanol to the tank as it absorbs the water and it can then be easily digested by the engine.
     
  2. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    I think #2 is going to help quite a bit- this is what was missing from earlier attempts. A pint or two of gas dryer (HEET or similar) should work wonders on that situation.
     
  3. Terror404

    Terror404 Junior Member

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    Yeah, that is what I am going to do today. Only thing I can get my hands on now is 97% ethanol, I will mix it with fuel and see what happens.

    Does anyone know if I should leave it or turn over the engine right after I mix it with fuel?

    Meanwhile I will clean EGR and Intake manifold.
     
  4. mr_guy_mann

    mr_guy_mann Senior Member

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    What does Techstream show in the freezeframe data? How would "water in the fuel" cause the ECM to set a fault code in the throttle body? Whatever is going on certainly could be thermal and intermittent, but I am not seeing any solid connection between refueling and your problems.

    Posted via the PriusChat mobile app.
     
    Terror404 likes this.
  5. Terror404

    Terror404 Junior Member

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    Neither would I if I did not know the prologue. Car stalled just at the first junction after refuelling. I towed it after and cleaned the throttle body, checked the wiring. Still the same problem. After I drained whole tank, car stated and drove normally for over 500 mls.

    update: Today I took off the intake manifold,throttle body and injectors and cleaned them. Could not clean EGR though, it got dark. They were dirty but nothing super mind blowing. Just some tar from 110K miles.
     
  6. Terror404

    Terror404 Junior Member

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    Four
    quick upd here.

    I dismantled throttle body, intake, egr and injectors and cleaned them, although they were not that dirty.

    Started the car and it had same syomptoms. p2111 code, throttle body stuck open, while it is actually closed.

    As I am stuck in countryside and cannot buy throttle body to see if another one will do the thing, is there anyway I can test it by multimeter? I do not have the repair manual to check which wiring is what.