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Thread: Mis-fire

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    Jedi Hopeful
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    Mis-fire

    This morning I developed a mis-fire at high RPM. (over 2000). Almost felt like I was running out of gas.
    The car still runs fine at low RPM. My first step is to check the spark plugs, then the fuel filter.

    Any other suggestions on where to look?

    Steve

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    Yoda
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    Re: Mis-fire

    My experience has been if the engine pops then the spark is cutting in and out and popping the fumes when it reconnects. If it bogs down, then it is a fuel problem--generally. I had a problem once where the needle and seat on the float was doing something weird and caused a miss at higher RPH. Replaced the needle and seat and fixed it. I chased that miss for some time before I finally replaced those parts. I like to read spark plugs also. Tr3s are famous for running rich. Sometimes it is the choke other times weak spark which can be plug wirers, weak coil, points, rotor, bad connection ect. I would do a check on the valve lash if that is a possibility of being out of adjustment. The books say like every 2 thousand miles for the valve lash, but I think that is if you are a racer.

    steve

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    Re: Mis-fire

    I have to replace my #3 spark plug every 500 miles or so or it fouls and misses.
    60 TR3A TS66043

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    Re: Mis-fire

    Well I fiddled with it and tweaked a few thing and it runs great. I cleaned the in line fuel filter, checked the float bowls, wiggled everything and have no idea what fixed it. I'm pretty sure it was a fuel problem. I'll run it tomorrow for a longer test drive and see if the float bowls empty out after a long hard run. Spark plugs are black but not fowled. All connections are tight. Valves were checked a few hundred miles ago. I'm also going to put more gas in the tank.
    Thanks for the help. These cars are a constant mystery.

    Steve

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    Jedi Trainee Joe Schlosser's Avatar
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    Re: Mis-fire

    You consider 2000 rpm a high speed Miss???
    Joe Schlosser
    SCCA National License, Retired
    60 Bugeye, since 1966
    SCCA FP, sold but not forgotten

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    Yoda CJD's Avatar
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    Re: Mis-fire

    Quote Originally Posted by Joe Schlosser View Post
    You consider 2000 rpm a high speed Miss???
    I have a set of 1927 mechanic’s manuals. One of the most interesting things I got out of reading them was that in 1927 2000 RPM was considered very high performance! That didn’t change until WW2...as usual war advances technology faster than peace time. Remember these cars are much closer to pre-WW2 than they are to today!
    John

    1955 TR2

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    Re: Mis-fire

    I keep my car between 500 and 3500 rpm. So "over 2000" is in the upper half. Everyone understood the point.

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