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Help Troubleshooting Auto Tranny Shift Problem

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Old Aug 15, 2006 | 08:14 PM
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Default Help Troubleshooting Auto Tranny Shift Problem

Hi everyone. I'm working on my '78 with factory automatic.

The thing doesn't wanna upshift under WOT conditions. Or even just close to WOT. As soon as I back off the throttle though, it shifts nice and firm.

Could it be the vacuum modulator? The transmission fluid is at the right point, and it downshifts just fine when I put my foot in it.

Cheers!
W
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Old Aug 15, 2006 | 08:24 PM
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Did this just start happening? Does it just not want to shift to overdrive at WOT or will it not even come out of first if you floor it? Lastly, what's the transmission in your 78...TH350,TH400, 700R4, etc...
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Old Aug 15, 2006 | 08:33 PM
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Along with the questions above, does the car have a detent cable from the carb to the tranny? If so, your description sounds like a misajusted cable.
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