misfire at mid RPM

Discussion in 'Engine/Drivetrain' started by Justin Danger, Jun 26, 2020.

  1. Justin Danger

    Justin Danger Addict

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    Hi all,

    I'm having some issues with my 22RTE. I've been doing a lot of driving around at speeds under 60mph, and so much has been wonderful. I recently started a new job to which I commute 10 or so minutes on the highway. I am now experiencing issues at highway speeds between 65 and 80 (haven't gone above that). That is when my RPM range is in the 2300 and up range. It feels as if I am hitting a divet in the road every second or so. My wideband has a graph readout option, and at those times it looked like saw teeth. Usually traveling at a constant speed, the graph is fairly flat.
    I've been playing around in the driveway, and sure enough I am having issues with misfiring around the 2300 to 2700 RPM range. My first suspect was the TPS, so I unplugged it, and the problem persisted. I have a new fuel pump, new fuel filter, and everything ignition wise is new (plugs, wires, cap, rotor, coil). I'm trying to figure out what the issue is.
    Have any of y'all heard of this? have any of y'all experienced this? I would love to take some road trips to remote areas again this summer, but am afraid of an engine that can't go above 60mph.

    thanks for any input!
     
    Last edited: Jun 27, 2020
  2. Justin Danger

    Justin Danger Addict

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    Timing is set, valve clearance has been triple checked, Idle speed is solid.

    New TPS is coming in today, I will install it using the trusted 4crawler's technique and see what happens. I will also try the tin can strip EGR block to eliminate that system as a problem.
     
  3. jetas

    jetas Grand Toyotaholic

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    Have you checked the flappy box on the intake?
     
  4. Justin Danger

    Justin Danger Addict

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    uh... AFM? I recently checked it when I was having issues a couple months ago that turned out to be a bad fuel pump.

    The TPS came in and I installed it as well as blocking the EGR. Took a drive and had no issues. Next I guess I will just pull the tab of tin can I used to block the EGR to see if that was the issue, or if it was indeed the TPS.

    When I rebuilt the engine I cheaped out and bought an O'reilleys TPS. The new one is from LCE and actually says TOYOTA on it, go figure it works better haha.

    20200627_113244.jpg
     
    Last edited: Jun 27, 2020
  5. RaceLab

    RaceLab Newbie

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    grab your wire harness where it leaves the inner fender and heads over to the intake and injectors and start wiggling it around... I've seen several harnesses with broken wires in that area that cause odd misfire issues.
     
  6. Justin Danger

    Justin Danger Addict

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    I recently went through the entire harness in the bay and neatened things ul as well as soldering all of the factory crimp junctions on the injector wires.
    It seems as if the TPS was bad. I replaced it and have been able to drive at highway speeds without the misfire being aparent.
     
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  7. Clay

    Clay Member

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    For future reference, Toyotapartsdeal.com is a good place for stuff like the TPS. OEM parts and what not. Cheaper than LCE as well.
     
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  8. Justin Danger

    Justin Danger Addict

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    good to know! I was getting their billet water pump pulley as well, so combinin orders was easy, but i will definitely check out Toyotapartsdeal.com for future stock parts, thanks Clay.
     
  9. Justin Danger

    Justin Danger Addict

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