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C3 Turbo 400 Transmission Problem

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Old Oct 15, 2016 | 09:52 PM
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gnbrown's Avatar
gnbrown
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From: oxnard ca
Default C3 Turbo 400 Transmission Problem
Hello Folks, My transmission just recently started to down shift back to 2nd gear when it should not. (low speed and while giving throttle) then I have to feather the throttle to get it to up shift back to 3rd gear. Any suggestions or help would be much appreciated.
Thank you,
Gary
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Old Oct 16, 2016 | 12:48 PM
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C3 of Year Finalist (appearance mods) 2019
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Check the modulator, vacuum lines to it, and the adjustment of the electric kickdown switch to start.
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Old Oct 16, 2016 | 06:51 PM
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Yep. Either the vacuum modulator is bad or the vacuum line going to it is partially blocked or leaking.
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