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  • power loss

    While driving under no specific conditions, engine lose a bit of power, accelerator becomes less responsive and fuel usage increases. If I accelerate a bit, back off and repeat 2 or three time, the vehicle will burst back into life and fuel economy returns for a while, until I repeat the procedure. Any ideas welcome. Thanks.

  • #2
    Has it thrown any diagnostic trouble codes if you put a scantool on it?
    how many kms you have on it now?

    Comment


    • #3
      Thinking of symptoms and probable causes without seeing if any DTC’s I would start looking at the actuator/ vane side of the turbo. This is just one possible cause but you have to start looking somewhere, it’s a process of elimination.

      I asked an old student who managers a Toyota dealership workshop and he has seen this symptom yet.

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      • #4
        Mate took the car for another run with a handheld tool (Careful how you respond to that) When either sluggish or pumped up , when accelerating, the map jumps to 170kpa About 12psi) boost, the egr valve closes to zero and at 100kph the rail pressure jumps from about 135/140 thousand kpa to about 170 thousand kpa. Either sluggish or pumped up. Wierd. Test was done starting at 100kph in fifth gear. No dash lights appeared. No codes registered by hand tool..Cheers.

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        • Spook1205
          Spook1205 commented
          Editing a comment
          There is nothing wrong with engine management system by those numbers and what’s going on with symptoms.
          Let’s go completely left field here and see if you have grabbing brakes

        • Spook1205
          Spook1205 commented
          Editing a comment
          Driving a fortuner I thought you would need two hands for that tool, did someone else drive?😂

      • #5
        could it be a sticking transmission / brake fault of some kind?
        2016 GX , in White

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        • #6
          A grabbing handbrake from being oversdjusted by using the cable is a reality. A dealership no matter the manufacturer do this. Handbrakes need the little shoes adjusted internally but that means removing a caliber and disc. It is adjusted till shoes just touch the inner disc drum then backed off 3 clicks do it is close but completely clear. It does have a symptom of mainly locking up in reverse.
          An over adjusted master cyl pushrod can cause brakes to grab and lock on.
          Dealership techs don’t do this because they are expected to work at 120% efficiency.

          I guess a relevant question is has Davidd had any work done on his car when this happened or not. That can eliminate that side of things.

          Diagnostics is a process of elimination from identifying possible causes from the symptoms. Testing for validation of cause.

          Comment


          • #7
            Two things mate.
            Could a partly blocked DPF cause the problem because is a bit of a problem?
            When I bought the vehicle the handbrake operated on about 4 clickes of the lever. Then it was changed to almost needing th full travel of the lever to operate it. Now it is back to about 5 clicks again. Are these handbrakes self adjusting because I have a downhill driveway and reverse out of it two to 5 times a day requiring some braking power to stop the car. The abs system used to work well but we had some really heavy rain here a while back and when I turned right at the traffic lights quite slowly, the abs light lit up and the vehicle went into substantial rear wheel slide requiring oposite lock on the steering wheel to correct. But no sound of ABS working or indication it was. Could the ABS system have been adjusted back by the dealership at a service perhaps. I set up a few slides at later intersectons and it slid out at very low speeds and always needed correction to control the car in spite of dash light showing system was operating.
            Now there's a heap of questions.
            Cheers.

            Comment


            • #8
              The DPF seems unlikely in the symptom / cause side of things due to other symptoms like excessive white smoke and a partially blocked DPF won’t be intermittent. Is it easy to check to eliminate it as a probable cause? Yes it is, you just need a multimeter and paper clip. I have put a few things on the forum on how to check this. Then at least you know it’s ok.

              The handbrake to me would be a highest priority to check out.
              It’s been played around with and most likely never adjusted properly. It needs 3 clicks of adjustment clearance on the actual handbrake shoes with the cable backed completely off. Then cable is then adjusted to give at least 7 clicks on lever, this is needed when running rear discs with the tiny handbrake shoes. 5 is not enough unless you are running complete rear drums / shoes and cylinders like the Hilux.

              Did it come back from a service being 5 clicks or has it worked its way down by itself to 5 clicks?

              I am 99% sure it’s not a self adjusting style mechanism. I have only had rear discs off twice to adjust and did not take that much notice. The ones that are require handbrake application not foot brake They don’t normally self adjust very well and should never over adjust. But in saying this sometimes stuff is so left field you can’t seem to think how did that even happen but it does.

              Can the ABS / vehicle stability control can’t be backed off.
              The ABS program can be tested on some gravel with hard braking. Sound like you have tested the vehicle stability control and it’s not what you seemed it should be.Take into account being a 4wd it’s not as delicate as a normal road vehicle. They can slide out a fair bit, I found this out on Fraser Isl.
              If electronic brake program senses any fault it will turn off and dash light will come up. It will throw a diagnostic trouble codes most likely starting with “C” (chassis). E.g C1278 = steering angle sensor fault. So if no codes present vehicle will / should be as it’s meant to be.

              hope this helps

              Comment


              • #9
                Checked it just now. Brake lever holds on 4 clicks, 5 is a firm pull and could be used on a heavy incline. 6 would be enough to do damage I think. Something I forgot about, but may be normal. If stopped at the traffic lights for a full cycle on a main highway taking a few minutes, the acceleration on take off and the next few gear changes is awesome, but then goes back to normal.
                Cheers.
                Last edited by davidd; 22-01-2018, 02:32 PM.

                Comment


                • Spook1205
                  Spook1205 commented
                  Editing a comment
                  That’s way over adjusted mate, worth looking into that.
                  If you want to drive to Werri Beach couple of hours south of Sydney I’ll fix it for you

              • #10
                Thanks for the offer mate but it's a long drive from Perth. I think it's worked it'sway down to 4 clicks. Maybe the brakes are self adjusting. live on a sloping street and have a sloping driveway. When I reverse out I reverse down the driveway and turn the back end down the sloping road before braking to move forward. Would be a fair load on the brakes in reversing out the driveway. If they are self adjusting this could be the problem. Quite often when the engine i a bit cold it has a problem taking off from rest at low revs and engine shudders a bit.. Once warm it seems fine. Cheers.. .
                Last edited by davidd; 24-01-2018, 09:46 AM.

                Comment


                • Spook1205
                  Spook1205 commented
                  Editing a comment
                  I’ll check the adjustment out more next time I pull it apart.
                  Shudder on take off when cold is a different story then. They may have to start looking at injector failure which is rare but I have heard of.
                  Perth is a bit far away hey

                • tekka maki
                  tekka maki commented
                  Editing a comment
                  You could try using the "idle up" switch for the cold engine problem, although it's really just there for getting started in much colder climates. As for the power loss, are you driving a manual or an auto? If auto, does the problem happen in both "drive" and "select" mode or just "drive"?

              • #11
                Long walk mate. But thanks for the offer. Yeah I Had thought of bad injector. Noises from engine, rough edge to engine, intermittent heavy fuel use, particularly at low revs, loss of power on and off. ill follow it up, Unfortunately I have no access to a diagnostic tool. Cheers.
                Last edited by davidd; 24-01-2018, 11:51 PM.

                Comment


                • Spook1205
                  Spook1205 commented
                  Editing a comment
                  Is your vehicle still under warranty?
                  Please keep posted on outcome
                  Cheers
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